You might find that investing in a reputable guide, such as Anal Pleasure & Health by Jack Morin, would make you both more comfortable.

My experience is that I cannot truly relax with the preparatory enema. A small to medium vibrating plug is also a great distraction to the actual insertion of the toy. Patience and plenty of foreplay and lots of lube are your best allies. My first experience took an hour or more to...consummate, and there was no pain.

Anal sex should not be painful...uncomfortable, yes...but not painful. Anaesthetic cream is not a good idea, as it can mask pain that would indicate more time, lube, etc., are necessary. The lining of the rectum is actually somewhat thinner than the vaginal lining and therefore more susceptible to abrasion or laceration.

The whole idea is to make him/her love it, right?

Happy tails!