I like to do different variations of basic stretches. I've been PE-ing for about 3 months now so I still consider myself new. I like to do BTC (between the cheeks) stretches. Basically it's like an intermediate downward stretch. You pull down and back between your buttcheeks and hold... much like the Adam Sandler song Medium Pace where he talks about looking like and ugly woman

. Anyways, it really works well. Also try some inner penis stretching early on too to train the part of the penis that is inside you.