If you're a regular reader of the Moz blog, chances are you've heard about the importance of investing in mobile. You've already formed an opinion on whether or not you'd like your employers/clients to build a responsive site or keep a separate mobile site, and you've started hinting that great mobile sites are worth the investment. The problem is, how can you make that happen?

In my experience as an SEO consultant, in order to effect change, you have to:

• Convince key players that change is important
• Know enough about the problem, the site, and the available solutions to recommend the best strategy
• Be an active player in the implementation, making sure that the solution is implemented properly, and that the change doesn't create any new SEO problems

Using that framework, in order to get a mobile site built, you have to explain the necessity of creating a solid mobile site, investigate the options of responsive versus separate mobile sites (or a combination of the two), and guide the build and implementation of the mobile site. This is your guide to making that happen.

Why you need to invest in mobile

Mobile isn't a small amount of internet traffic anymore:

Source: http://www.slideshare.net/kleinerperkins/kpcb-internet-trends-2013

Mobile internet usage has grown dramatically in the past few years, and as cell phones and data plans get cheaper, mobile visitors will become more crucial to online success. It's easy for site owners to push aside the 10% of visits that were coming from mobile last year, but what about the end of 2013, when 20% of internet traffic is projected to be mobile?

(Also, do you notice how there's a spike in mobile internet usage every year in December? Aim for a November roll out of your new mobile site to make sure that it's up and ready for the influx of mobile visitors you'll get after the 25th. Bonus points for devising a mobile-specific marketing strategy in early January.)

All right, so a lot of people are using their phone to go online. But how does that translate into conversions?

For ecommerce

There has been a lot of discussion about mobile conversions, mostly because:

According to Google, 35% of mobile visitors in 2012 have made a purchase on a smartphone. Keep in mind that only two thirds of all internet users have made online purchases, meaning that mobile visitors are really only about half as likely to make a purchase as a desktop visitor (and these stats back that up). And by "half," I mean that-glass-is-half-full: mobile visitors are half as likely to buy online as desktop users already, and as the web becomes more mobile-friendly and people get more used to relying on their phones for purchases, that number is only going to increase.

For offline companies

What if you're working for a company that doesn't sell its products online? That almost makes mobile more important. 70% of shoppers used a mobile phone while shopping during the 2012 holiday season, and 62% of those shoppers looked at the store's site or app. Giving visitors a great user experience can actually increase offline sales. If you're working for an offline retailer, consider building a site that will aid in-store sales, offering things like coupons, reviews of in store items, and more product details.

For informational sites

Last, many companies that provide articles and content rather than products think that visitors wouldn't want to spend the time reading their long form content on a mobile device, assuming that mobile visitors only read sites "on the go." But The New York Times put the effort into creating great mobile sites, and now one third of its traffic is coming from mobile devices. Mobile visitors will be able to read your content sitting on the bus, riding up elevators, and waiting in store lines.

Convinced yet?

If not, look through the masses of statistics on Karen McGrane's State of the Mobile Web - Sources post and find what speaks to your situation/site. There's just too much information out there for some of it not to be pertinent to you.

Once you've put together an epic presentation on the importance of a mobile site and convinced the right people, they're going to need some guidance planning the new mobile site.

Too many options

Choosing how to build your mobile site can be confusing and stressful, mostly because there are so many different options. You could build a separate site, with separate URLs. You could build a separate site that is served in place of the main site when a mobile visitor tries to access the page. You could build a separate site that is a (smaller) mirror image of the main site, or you could build a mobile site that is completely different. Or, of course, you could build a responsive site.

The reason there are so many options, and therefore too many choices, is that you're trying to answer two very separate questions with one answer:

1. What content do you want to offer to your mobile customers, and
2. How do you serve that content?

Content

There are really only two ways you can build your mobile site: Either it has the same content as your main site, or it has different content.

Before you worry about the technology, or what exactly it will look like, you have to decide what your goals are for the mobile site. Are they the same as your primary site, or are you focusing on different conversions? Or (and this is an acceptable answer), are you considering building/improving your mobile site because the statistics at the beginning of this post freaked you out?

The key here is to figure out if visitors' goals on the main site should be the same on the mobile version of the site. This is partially determined by what you, as the business, want your visitors to do, and partially by what they actually want to do. You should determine your business goals internally, but use your web analytics to see what mobile visitors are doing on your current site.

If you and your customers want the same things from the mobile site that you do from the primary site, you probably want to build a mobile site with content that's identical to your primary site, unless you have the time and desire to regularly modify the mobile version. For example, SEOs who want to tweak their mobile sites so that they target slightly different search engine queries and browsing behaviors will want to build a mobile site that can be independently modified.

Technology

Now that you've decided what content you want on your site, you can start to look at how to make that come to life.

Responsive

If you decided that you want to build a mobile site that has identical (or near-identical) content to the main site, you may want to consider building a responsive site. Some of the pros of a responsive design are:

• Once you've built responsive templates, you don't have to update both the main and the mobile sites separately.
• When you only have one version of content, and you know that the mobile version will show up on a tiny screen, you may find yourself editing your content better, which is good for your primary site as well.
• Links that point to your desktop site will also point to your mobile site, making it strong even though it's new.
• Your site will amaze visitors (other SEOs/web designers looking for examples for their blog posts) as they change the browser size.

Resistance to responsive sites

"Building a responsive site would take too long/cost too much, because it would involve rebuilding the main site as well."

To save money or spread the costs out over time, you can either build a separate mobile site, roll out the responsive site slowly, or do a combination of both.

To "roll out the responsive site," identify the pages on your site with the most traffic, and make them responsive, doing as much as you can in increments until the entire site is responsive. A benefit of this is that you'll get feedback from customers as little chunks of the site become responsive, meaning that the problems won't affect the entire site.

If you decide to just build a separate but identical site, use the same URLs for your mobile sites, but have your servers deliver the mobile version of the site to mobile devices (this is called dynamic serving). That way, you can start working on rolling out responsive design later and don't have to deal with broken URLs.

"The content on my site takes too long to load on a mobile device."

There are a few different types of content, so I have a few answers to this:

• Text actually doesn't take that long to load, and research shows that mobile visitors are actually quite willing to scroll through long pieces of content. Though, if you really want to hack away at the text that's on your desktop site, why not just hack away at it on the desktop version of your site as well?
• Images can be served dynamically so that mobile devices are offered small, low-resolution pictures while larger devices get higher quality.
• Complicated JavaScript/CSS can usually be simplified without giving up too much of their functionality.
• Flash just shouldn't be on your site at all anymore. Just let that technology go, everyone, we have HTML5 now.

Separate mobile sites

If, on the other hand, you've decided to create different content for your mobile visitors, you'll want to go with a separate site. Pros of separate sites are:

• There are no limitations from the main site, meaning:
  • The site can be completely different, targeting mobile users' needs more directly.
  • The site can be largely the same, but tweaked to target mobile users' keywords and mobile search engine results.
• The main site doesn't have to be redesigned at all.
• The initial build will be easier, since you don't have to set up CSS media queries to lay out.
• If there is a lot of bureaucracy around the main site, you may have more flexibility to test new ideas on the mobile site, which you can roll into the main site if they're proven beneficial.

Resistance to separate sites

The only real resistance to separate sites is the idea that responsive sites are better.

The cool thing is, building an awesome separate mobile site does not mean that you've passed by the opportunity for responsive, if that becomes the big thing. Mobile First, by Luke Wroblewski, theorizes that building a responsive site from a mobile site is actually easier, and in the end, lays a better foundation for a great responsive site.

Make it happen

I'm not a designer or a developer. If you are both, congratulations, you're awesome. Go read Responsive Web Design to build your new responsive site, or just start writing some HTML for your new mobile site.

If you're an internet marketer like me, check out the guide that Bridget Randolph and I wrote on designing, helping with development, and tracking mobile sites: http://www.distilled.net/training/mobile-seo-guide/

Good luck!

Getting a great mobile site built is still an uphill battle, but it's definitely worth it. For those of you that have built great mobile sites already, anything to add? For those of you that haven't, any questions I didn't cover?