Desire; desire is the first thing because you’re dealing with muscles that you have to have the ability to relax, and if you can relax these muscles, the body is much more accommodating. It's much easier to have great anal sex when you really want to do it. It doesn’t feel good when somebody is manipulated or somebody gets a sneak attack, and the person doesn’t know that it’s coming. They don’t really have a chance to relax their muscles and be ready for it. That’s the opposite of desire, so I always say desire is the first thing you need. If you don’t want to do it, don’t do it. It just doesn't work.
The second thing you need for great anal sex is lubricant. The butt is not self-lubricating like the vagina, so lube is essential.
Finally, you need a partner you can trust. You can also experiment on your own body - if you're hesitant or curious - to see what anal penetration feels like. That way, if you do decide to try it with a partner, you'll feel more comfortable and ready.
And one last thing: when it’s done right, anal sex should never, ever hurt. It should
never hurt. It should feel good, and it could feel weird - like you’re pooping backwards. If it hurts, something's gone wrong.