Baitcaster??? Need some help!!?

Ok so today i got my baitcaster in the mail, put some 8 pound trilene smooth casting on it, put the reel on a shakespear 5'7 ugly stick. I used a jointed rapala. First time i casted it went smooth ( first time ever using one) second cast i casted it out and got a massive nest. Does anyone know what the dial on the side ( 1-10 ) means and if drag is important? I plan on going tomorrow again so i also need help detangling it. Thanks all