That is the one hint most often overlooked when I have seen advice for newcomers to pegging, and it can make a world of difference in your initial experience.
Your anal sphincters are built to open up and let things out, but not to open up and let things in. So the first few times you are penetrated with fingers, toys or a dildo, you must learn the trick of consciously opening up that sphincter.
How do you do that? By acting like you are trying to have a bowel movement. Exactly like that. You bear down and kind of push out. This allows your anal sphincter to open and then allows penetration.
I have had some interesting questions asked about this technique:
Won't I take a shit if I do that?
No - not if you have already emptied your bowels (which anyone getting ready to receive anal sex should do), there is nothing in there. Shit does not magically appear just because you bear down.
Won't I squeeze the dildo out?
No - on the contrary, it will help the dildo/toy/fingers go in.
Are you sure I won't take a shit?
Positive. Just make sure you empty your bowels before play.
So that's your hint for the day, ladies and gentlemen.
Then write and tell us how it went.... 🙂