I read in your comments that you are 29 and your wife (partner) is 22. You can definitely try anal sex, but ensure that your partner is also willing to give it a try. Absolutely no force, or that will ruin your fantasy and your partner will never try it again.
There are some points to consider:
1. Don't insist on penetration
Although it's hard to believe, you don't need to stick your fingers or penis inside the rectum for the pleasurable sensations associated with anal sex. And although it might be a bitter pill for some guys to swallow, when you're receiving anal sex, you don't need to have anything put inside you either. By simply rubbing the anus or even licking it, known as rimming, the receiving person can derive awesome sensations.
2. Make it feel good all the time
Many women have said that their first anal sex experience (and sometimes their second and third) hurt like hell. Now, if she isn't calm and relaxed, it's going to hurt. If you insist on shoving your penis inside her (like ripping off a bandage -- one shot), it's going to hurt. If you don't use lubrication, it's going to hurt.
You need to talk about it and both of you need to agree to do it happily; no one should be coerced into it. You also need to be patient and let her lead the way. If you are going to engage in anal sex, let her hold your penis and guide it in slowly. Go in about an inch, then pull out completely, then go in about an inch farther and pull out completely. Keep going in and out at one-inch intervals and pretty soon you'll be in.
3. Understand that there are 2 sphincters
There are two sphincter muscles in the anus and they are less than an inch apart. While you can control the external sphincter at will, the internal sphincter is not the same. It reacts more in a reflexive way. So while your partner may assure you that she's relaxed and willing, her internal sphincter may prove otherwise. The point is that you need to be patient and give your partner time to learn how to relax and try different positions to make it happen.
4. Stimulate the anal region while doing other things
The sensation of touching the anus or rectum alone may feel uncomfortable for your girl or even yourself, but couple it with Penetration or oral sex, and suddenly it'll feel much better. For example, while you're engaging in vaginal sex, you can insert a sex toy into your girl's anus to give her the sensation of double penetration. And she can insert a toy into yours while you're penetrating her or she's performing oral sex on you. It's up to you to decide what you're both comfortable with.
5. Change your diet
For a pleasurable anal sex experience, it's important for both of you to eat a diet rich fiber, raw vegetables and fruit rather than processed foods. Regular bowel movements are conducive to both comfort and confidence when it comes to anal sex. Try to avoid eating it for a few hours before you're set to engage in anal sex.
6. Obey the rules of hygiene
There's a reason why women have to wipe from front to back when they do No. 2; trace amounts of feces may cause infection. The same rules apply to anal sex. If you put your penis or fingers in or around her anus, you cannot simply revert to her vagina afterward. You can always discard the "anal sex" condom and put on a new one for vaginal entry.
As for your fingers, you can always keep baby wipes close by and wipe your hands before you use them on her vagina. Remember; you can go from the vagina to the anus, but not the other way around. Hopefully you know your female anatomy.
Ensure anal sex is fun by making certain that you and your girl are comfortable. If she gets squeamish when you suggest it, find out why. Don't be afraid to communicate about sex and what you like; it'll bring you closer together and enhance your sex life.
Keep in mind that anal sex can be very dangerous and spread STDs, so unless you're in a monogamous relationship and you've both been tested for diseases, I strongly urge you to use condoms and latex barriers in anal sex and any other variety of sex.