I joked about it. You know,talked about it so see how my partner feel'd and if he got always blushed or nervous. That happened sometimes. It really leads to conversations about it. Just JOKE about it, don't be too serious. Buttplug-jokes work like a dream, he might check those out and start discussing those himself.
Talk about your "friends" to your partner. Say that they tried it, you can lie. Nobody ever finds out. Maybe just tell that they did it, nothing else. That might get him interested. This usually works.
Long ago. Tell that you have "tried" it long time ago, while young. Don't tell that you fucked yourself in the butt, tell it sweet. Tell that you made some love there, or just tell that you touched yourself from there. He might get interested how it feeled. Don't say that it was great, say that it felt ok and different. Otherwise you sound desperate.
These will take time, but you will get it for sure. Patience is a virtue.
Now some words how to make it feel better for your partner, so you'll get it gain:
There is just not too much of this. Rely on it.
Being girly. Use girly high-pitched scream while he is touching your 2nd hole. Exaggerate! Tremble with your whole body. But not too much. Dont just grab it and guide it in, be "ashame".
Use your face. Make a sweet smile, pretty smile, but show like it too much. Make him happy and he will make you feel good. Make him feel it is too much for you to handle, and it will!
Talk to him. Not dirty, but how sweet it is. How natural. It doesn't have to make much sense. I usually tell him how I feel like I'm "his pretty little princess" while he is doing my butt, and he likes it.
Use you body. Squeeze it out and in randomly. Move those hips. One trick from me: This makes my man crazy: When he does me in Press or Full Press (or something similar, where he sees your foot and ankles), point your toes hard. Say how that love goes through your body and you feel like dancing on him. That you feel like being a ballerina. Always point those toes!
Doggy style feels old? Some good positions for anal:
Laying rear entry. My favorite. Lay on yout stomach. Pile up pillows under your hips to make you raise your butt. It is forced and he cannot hurt you. Spread and point those toes to make him come to you. You can make some gymnastic stretches. Close your feet if he comes too deep. It is easy to control, but you are still in the bottom. Lots of friction inside you!
Spoon. Many people consider this the safest way to practice anal sex. It might be. It feels so good, he wont come too deep, but you can really use your body to control the situation somewhat. Moving your hips makes him crazy!
Squat/Rear Squat. This is the ultimate deep penetration. And so romantic! Just sit on his laps and feel it inside you. Controlling your body is so fine and it makes him easy to kiss your neck and play with your hair.
Paired feet. Designed mostly for anal and some people love it. I have sometimes hard to take it in but if I trust him, I would always try!
Leaning in. You're afraid and shy? Try this. Just make him lie down on a bed, and ride him backwards. Don't jump, just slide on him. He will love it. I still don't think that it is wild enough, but I don't wonder why people can love this. Sometimes it just works.
Splitting. Girls favorite, but they feel it boring and sometimes even awkward. Girl doesn't split, so they wont see you and one guy felt it was for monkeys. Still, they go so deep and rub your behind so hard that I would like to do it more often.