I found this video the other day and I have found it quite helpful. I play a big 6 string and have pretty small hands. I have also spent the last few years fighting tennis elbow and other chronic tendinitis. My injurys are from chainsaws and shovels but playing that big bass hasn't been helping. Anyways, from the garry willis style hand movements to the low slung death metal bass between the knees... this guy has some good tips.