Other than don't? Haha, just kidding. Contrary to popular belief it's not something that is easy to accomplish and if you're interested in doing something like that and getting a real check for it, then you should probably start treading in those social circles. Look for adult conventions, toy shows, and live webcasts with stars and start finding out how they got into the industry. Every story is different, but they all have pretty much the same beginning. "I knew a guy who knew a guy who knew a guy and the next thing I know I was signing a contract to be a Digital Playground girl".

I don't have any personal experience in this, but I would recommend trying to find someone who already has some experience as the field and have them mentor you in the process. I am guessing that it's not that easy to get into (or to be successful at), but if you have someone who knows a thing or two about the business I bet that would be a big help.

make a website, spam everyone

Join a couple of websites with good exposure. Apply with every website you'd be interested in working with.

Create a website, blog, tumblr, twitter, and/or facebook and post at least a couple of times per week. Get your name out there. When you create the website, think hard about the search terms that people find you with and don't use direct quotes from anywhere else. Google will filter out duplicates. You should also make sure that you register your website anonymously, or you might have to worry about stalkers.

Please note that if you're taking a more independent route, and not just using a website for promotional reasons, you will have to figure out safe modes of payment, legal stuff, etc. Do some research on that. OR this could be useful. Doing this independently will be MUCH harder than with a website, but you'll get a larger chunk of the profit, will have less rules, etc.

I have no idea if you're interested in camming, but that can be an excellent place to start. Lots of women on myfreecams and mygirlfund sell photos and videos in exchange for tokens. You will generally have to give live interaction first, though, so people can get to know you. But once you get a following, you can primarily sell videos and pictures.

Hopefully my post was helpful.
If not, there is a ton of information on promoting yourself on stripperweb.com.

Good luck!

A lot of 'porn stars' moonlight as camgirls. You could start there and see how you feel about getting naked in front of people and such. It's easier to network once you've really put yourself out there like that.

I'm a cammer and I declined a porn offer from a legit site because they don't test as often as they should.

Whatever you choose, just be safe and read all the fine print before you sign anything!