The bow that you have was designed to be shot "off the knuckle" so you did correctly with using your hand as a rest. I'm not sure if there are any special gloves for this style of thooting but i'd look into it. you'll want something foryour "string" hand as well. Something like a shooting tab or a shooting glove.These will help in a more consistant release and result in better accuracy.Another thing to invest a few bucks in (if you're hitting your arm) is an armguard. I would go ahead and get a more permanent finish for the bow because putting stuff on routinely seems inconvenient.

here are some links
http://www.3riversarchery.com/Cat.asp?c=1&s=0&p=0 <--- gloves, tabs, and armguards

http://www.3riversarchery.com/Thumb.asp?c=49&s=37&p=0 <--- bow finishes (alternative to petroleum jelly)


Also, when practicing with a traditional bow it's a good idea to change the distance from the target a random intervals. maybe 2 shots move, 3 shots move. This will help to train your mind to automatically judge distance to the target and make adjustments accordingly. I'm still a rookie to Traditional gear myself. good luck! and have fun.