I just did something that I always do before I start a section/song of a slideshow and I thought it would make a good tip...
Before you lay in your pictures or create any effects, play your music through and create markers at the beats throughout the song. If the song has any places where there is a natural change to the tempo or the beats, change your marker beats. When you are done you should have markers along the whole song which make it easier to create cuts, transitions and keyframes at natural points in the music. It's a simple tip but I think it will be good advice.