My one gelding adores getting groomed so I sometimes end up going at the barn a second time that same day just to take him out again and groom him. He loves it and it's great to spend some time with him.
I basically do it like most other people, Before I ride, and after I ride and often for a LONG time after i ride, sometimes ill sit int eh barn for another hour or two just fussing with him and sometimes if I bring my saddle bags I'll pack a few brushes and such and brush them while they drink from the creek or something or dismount and groom a little. I fuss a lot and groom a lot and my boys enjoy it.
For a while I was being really bad about grooming (and riding in general) due to time restraints and just was in a non-horsey mood.
Now that I am back into full on i-want-to-be-with-my-horse-day-and-night mode my horse is getting his grooming sessions back. (and his riding back too)
I groom him before and after I ride, then random grooming sessions just cause.
First I spray with conditioner
Then I brush him with a hard brush (spraying conditioner on the brush as I go)
then I soft brush
pick out the feet
brush the mane with my tail brush
every now and then I show sheen his tail like crazy and carefull brush it too.
He gets bathed before shows or every couple weeks during the summer. He gets sprayed down after every ride during the summer.
I groom my horse in his stall for before and after ride grooms.
I tie him in the aisle for long grooms or grooms where I oil his feet.
Also, I like grooming because it really helps bond with the horse. Think of it; a wild horse is nuzzled (or groomed) by a herd member, and they trust them. So they think of grooming like another horse grooming them in the wild.