Don't rush into anything that you are not ready to do. Start with lots of lube, fingers, move up to toys. Watch sexual material that gets you turned on and make sure you're rubbing your clit and keeping yourself wet while doing this.
When enough time has passed, you can surprise a favorite friend with benefits (if you have any) whose penis size you are comfortable with. If you prefer a client then don't auction yourself off, as you might get a one timer who will give you a bad experience. I would even recommend a regular that you enjoy seeing and just telling him you want to try anal and since he's been seeing you for a while that you're willing to make it happen with him, and charging him whatever rate you please. Maybe even make this your one session for the day and just take your time with getting comfortable and taking as much time needed. This may be something you end up doing more than once in that session. Get really lubed up, and for your first time you may want to be flat on your back and really turned on and wet while rubbing your clit and having the lucky fellow go in slowly and gently. Don't be afraid to have him pull out and start over again. Good luck!
Yeah that's what I've been told.... Also I was looking on the Internet on how to make it easier, do muscle relaxers work? As anyone used them before hand? Lol