This is my boyfriend's full head of 4a waves. He has really super thick hair and has been wearing it like this for about 6 months now.
He does not use shampoo on his hair very often. Instead, he 'washes' it with conditioner and then smoothes in Oil Sheen in a Jar. After that he brushes it flat and puts on a wave cap. Once it dries, Voila! Waves!