Use nylon-jaw pliers or a burnishing tool to gently smooth the prongs and bezels down onto the stones. For step-by-step instructions, see our blog post on setting crystal stones.
Use a 6mm jump ring to attach the "12" charm, and use oval jump rings to attach the other charms. Attach all charms to the center loop: this keeps them on top of the bracelet. (Otherwise charms like to sink to the bottom of your wrist.) For best way to open and close loops, see Jump Ring Hint in Jewelry Basics 101 (PDF)