Best ways to make Anal more pleasurable than painful?

So, i'm not into Anal, but a friend of mine told me that in his experience, Anal has always been more painful than pleasurable and that he doesn't really enjoy it (As much as some people seem to do). Then i read somewhere (I don't remember where) that Anal doesn't have to be painful at all, so that got me thinking, maybe my friend is doing something wrong, or maybe he's just not into it either. But anyway, does anyone with experience here have any tips to make Anal painless (Or at least make sure it's more pleasurable) for any future partner?