My 3-1/2 month old daughter used to hate it too (and still does at certain times). I found that if I put her on her tummy on the floor for short bursts (like 1 minute) and then roller her over or picked her up and just did it really often, she got to where she didn't hate it as much.
Other things she seems to like is when I get on the floor in front of her and get her to look at my face, then I sorta do a mini push-up (just lift my head and chest off the floor like I'm wanting her to do) and she seems to like watching my face go up. Sometimes it even leads her to mimmick me just because she's watching me so closely. There are times when she will stand being on her tummy for 15 minutes and then there are other times that she can't stand it more than 5 seconds! The nice thing is since their attention span is so short, even though they hate it at 10am, they may tolerate it a little more at 10:30!
Good luck!