I've taken the belly of the Hazel bow down with a spokeshave until flexed a good bit when I pushed against the grip with one end against the floor and the other end held in my other hand (this is known as floor tillering). I then put it on the tiller with the string adjusted so it would just go onto the bow. I've pulled it a bit to adjust it to a vaguely even flex on each limb, just 2 or 3 inches tip deflection. I don't want to bend it too much and make it take a set (permanent bend). I'll heat treat it now and then get back to tillering after giving a few days rest. Meanwhile I've narrowed the grip area a bit, just roughing it out.
I'm deliberately making it very assymetric so that it really sits nicely in the hand, and provides an accurate location for the arrow pass whilst still shooting off the hand rather than an arrow shelf.
I did this on my Ash/Cherry bow and it felt really comfortable.