Yeah those disks are great - take it you mean the scrunch up type ones? Get yourself another one, two are better if your taking pics of more than one person - use the silver or white ones for highlighting faces/eyes etc - the gold ones are magic for doing 'flesh' shots (lol) they give the models skin a healthy glow - best thing to do is grab yourself a willing friend or two, pose them up and practice till you get it!
Oh, and dont worry about looking stupid! Just get the shots, and you never know, some of the inevitable watchers may well be impressed enough to take a card from you! Go for it!