Learn proper access shapes and locations for molars, it matters. Go slowly, be organized, write your working length and master apical file size on a piece of paper once established. Don't get bleach on your scrubs. Trim your cone with a cone cutter, not arbitrarily with scissors. Save your best teeth for practicals but don't hoard, you don't need a "back up" when other classmates have none. Don't instrument past the apex with any file except an 8 or 10.