My DD gave a baby shower for one of her friends, because she knew that the mum-to-be desperately wanted one. It was a lot of work but went very well. She made lots of decorations on the "shower" theme, e.g. cardboard clouds with raindrops, rainbows, umbrellas, etc, and loads of yellow and white streamers. She also did the buffet (with my help) and created a lovely album containing letters from all the guests (written well in advance), offering advice and encouragement for the new mum.
She did draw the line at organising the games, though, and got another friend to do them. I remember there was "guess the baby's name and weight," and a blind tasting of "guess the baby food" and "pin the nappy on the baby." It was all a bit daft but mum-to-be-was-thrilled by it all.