My advice is to take it slowly, enjoy the process of discovery and let it happen at its own pace. Having that connection with your man through your ass can be highly sensuous and really mindblowingly erotic ... but Rome wasn't built in a day.
There are a lot of variables that can make anal sex pure pleasure or a real pain. I'll try to list some of the do's and don'ts as I have discovered them over time.
My first pleasant experiences with having a dick in my ass were when I was on my side and he was lying beside me in the "spoon" position. Fucking just sort of happened as things got hotter and heavier, just natural lube and it kind of slipped in and felt amazing.(unprotected, but this was a while ago.) It was just the right time for it to happen. I think it was more about stimulating my anus than the prostate at that point, but it got me used to having something enter me in a smooth and pain free way.
As time went on I invested in a dildo. I bit off a bit more than I could chew and bought the "Jeff Stryker". That was a challenge. It made a big difference for me in getting used to the different sensations of having something deeper and bigger inside my ass. It was a slow process as I would try for a while and then think that it was too uncomfortable and give it a rest for a long time. On again, off again.
Besides the purely erotic feelings and fantasies of being fucked there are other things available that make anal sex easier and more appealing. At some point I discovered "poppers" and this made a huge difference to my enjoyment of anal sex. Nitrites -- poppers -- are a substance that aids in vasodilation. Opens small blood vessels and relaxes smooth muscle in the body. Nitrites have been prescribed for some heart ailments in the past. There is a slight high that lasts for a short time, a rise in pulse rate and relaxation that can be very pleasant. I suggest you google poppers and get the low down.
Whether you agree with substances like poppers or not is for another thread. There are many opinions on both sides so I leave it to you to decide for yourself. My experience has been good and I have enjoyed using poppers from time to time to heighten the experience and to aid in relaxation. A little wine can ease things along too. Not too much, just enough works really well. More recently I have heard that a couple of Sudofed can be really helpful. The sudo-ephedrine (spelling?) and the aspirin combine to make the ass "hungry" and reduce the sting. Not sure why this occurs but many people that take cold medicine of this sort when feeling under the weather become oddly horny. I leave it to you to decide for yourself. Also, there is "weed" if you are into it.
Make sure you are well cleaned out. Don't over do it as this can irritate your ass, but be diligent enough that you are able to be relaxed and know that there won't be "traffic" to contend with mid fuck. Poppers during cleaning out can really help the process.
Use lots of lube. This is key to a pleasant experience. Too often we skimp on lube because it is expensive or we still have "a little dab 'll do ya" going through our heads. Hang the expense! Lube, lube, lube. If your partner is wearing a condom, and I assume he is, make sure the condom is well covered with the water based lube. Sometimes the latex can sting when it comes in contact with your ass, so make sure there is a generous lube barrier.
Understand that there are a few sphincters to be relaxed and passed as his dick enters your ass. Your anus has two sphincter muscles, an outer and an inner that need to be eased open. As he slowly gets deeper he will encounter another valve and this also has to be gently teased open. With time and lots of lube this one will relax and really heighten the inner stimulation. If, on the other hand, this inner valve is reluctant to open it can feel like you are being poked. Slow down, take your time and keep applying the lube as he enters. Water based lubes are absorbed by your ass and the water evaporates so re-apply.
When he gets all the way in you might want to begin pushing back onto his dick. Take your time to feel the sensation. Let your body accommodate the intruder and get used to it. After a while, if you are into it, you can have some poppers. This will open you up more and ease the natural reaction your ass might be having to expel his dick. Then let him slowly, slowly begin to move his dick. Let him tease your ass open and allow him to go a little deeper.
At some point you will feel the unbelievable sensation of having stimulation of your rectum, the inner valve I mentioned, your prostate and your anus all at the same time. Take your time, add more lube and keep going. It gets even better.
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When you are in the bath begin to explore you ass. Take time alone to open yourself between love sessions with your partner. The more you know about your ass and how it works and feels, the better. You might think of shaving or using a cream to take the hair away. Hairs get pulled and tend to make you think that the experience is more painful than it is.
Anyway, that should keep you for a while. My eyes are closing and I have written too much, but I hope this helps.
Cheers,
U.
