Make sure you are cleaned out. If there is stuff left inside, there is no way you will be able to relax sufficiently. Cleaning can be a real turn on. Can really get the motor going. Excitement and anticipation of the feelings you are about to have can also help to open your ass. Practice with dildos of increasing size. Amazing what you can take when you are on your own without performance anxiety. Go slowly on your own or with a partner. Use lots and lots of lube. Water based lubes have to be reapplied often as your rectum will tend to absorb moisture, so add more. Oil based lubes work well but can deteriorate latex condoms or toys. Find a position that works for you from an erotic point of view and a practical one. For instance, it might be easier to control entry if you are lowering yourself onto your partner, but this won't be the most relaxed position. On your knees with butt up and head down might facilitate entry most easily but you have to have good communication with your partner, insist of on frequent reapplication of lube and slow entry. Even if you feel you want to push back in eager anticipation of what's to come, just let him take care of the slow and steady entry. It will be a very hot time for you! Poppers help with this sort of thing amazingly. They will help to open your ass, make you relax and allow the 2nd (or 3rd) opening to open up so you don't get the feeling of "hitting a wall". Once his dick does get past the 2nd opening you will really know it. I found it to be a wonderful feeling of openness and euphoria. Make sure he enters really slowly applying more lube often. After a while he will be able to begin moving and finally increase his tempo. This is an amazing time. The feelings are like nothing else. Happy receiving!!