I wash my son's head with a baby brush and baby shampoo to prevent cradle cap, and even tho he has lots of hair i still put lotion on his head.
My daughter had it for awhile, and my son has it a little bit...use baby oil directly on the spots that are flaky..it's much better for cradle cap because it actually treats the scalp and it doesn't dry out the hair :)
Have you managed to get rid of the cradle cap yet? If you just leave it, cradle cap usually gets way worse before it gets better. I usually rub gently with a towel (after a bath) in a circular motion on the area that looks like it is developing cradle cap. After it has rubbed off I apply a small amount of sorbelene to prevent the area from drying out.