The best way to make a living wage is to make sure you live some place that is dirt cheap!
All kidding aside, I'm not sure you're asking the right question.
Generally, SEO professionals get paid by someone else to improve their (other people's) sites- either working for a company to improve the company's site(s) or as a freelancer (or part of an SEO company) working on improving other companies' sites.
If you are doing SEO for your own sites, that's only part of the equation- you don't get money simply by getting more visitors to your site. The key is monetizing your site's traffic.
At the end of the day, you could be the best SEO in the world and have amazing traffic to your site, but you'll still be starving if you don't monetize your site.
More SEOs should work on monetizing their own sites before they charge other people to help them monetize theirs. Nothing beats hands-on experience such as hanging on for dear life as something goes horribly wrong or riding the crest as everything lines up and goes according to plan. There's also a joy of discovery as you learn new coding tricks, the joy of taking an off the shelf WP template then customizing it for user experience in ways others never thought of. It's a great feeling to be a niche leader and watch others scramble to catch up with you. It's a good feeling to win an award, like I have, from a prestigious magazine. It's uplifting to receive emails from people telling you how much they love your site and to never ever sell it. It's awesome to sail through algorithms like Panda and Penguin and not be affected. But most of all it's awesome to receive payments from affiliate networks and ad clicks.
More SEOs should work on monetizing their own sites because it will make them better SEO professionals. Actively participating on WebmasterWorld is a two-way learning experience for me. I share but I get back. Same with Twitter and Facebook communities. I have a weekly thing on my Facebook page where I'll pick an area of SEO that I think is Bull**** and start a discussion around it.
1. Hands-on experience - Work a range of niches, even outside your comfort zone, which will make you work harder and possibly bring something to the niche no one else can.
2. Active participation on WebmasterWorld
3. Active engagement with social groups on twitter/facebook
4. Identify bright folks who are local to you and form a social group for dinners etc.
All those things will help you become a better professional.
All above, but there is also the fact that not everyone is cut out for "this" (the web, SEO, eCommerce, retail, wholesale, etc.) Like any job worth doing SEO is worth doing right... and like most jobs is a) boring and repetitive and b) dang hard work. You don't get to c) profits instantly and market signals and even the SEs themselves can give conflicting feedback.
SEO is details, details, details, and keeping after it day in an day out. It is not just something you LEARN, it is something you EXPERIENCE and in the process learn new things along the way.
SEO is only part of the equation. Without content or product you still have nothing even if you get a click to the site, which is where the whole thing should begin.
Monetizing is something else. That's not SEO, never has been. It's a completely different aspect of business on the web.