I recommend you look for someone in the local VCA to do it with you. Members here could give you the painful step-by-step on the forum, but if this is your first time rebuilding brakes and you are doing it because the pad went to zero and melted the dust boots, then you should have someone else's eyeballs looking at the carcass just in case there is more to fix.
For example, if the pads are very worn, then the pistons are greatly extended out of the caliper, further than they ever normally would be. If the dust boots are gone, then the sides of the pistons were exposed to dirt, pad debris, sparks... You don't want to just slap that one back together.