http://fiascofarm.com/goats/kidding.htm
While I don't agree with everything this website talks about, the birthing position pictures are really invalueable.
Earlier in gestation, usually 30 days post breeding, I draw blood for CAE/Johnes testing. I want to know status prior to kidding.
1 month pre-kidding, I copper bolus, BoSe, and Vaccinate.
Deworm at kidding with cydectin, I use pour on at 1cc per22lbs, or quest horse paste 1cc per 100lbs.
Increase grain intake and MAXIMIZE the quality of your forage 4-6 weeks prior to kidding.You don't want to totally rely on grain for improving nutrition. You wnat them to have some grain so they transition better onto a lactation diet, but you really don't need gobs of grain pre-kidding if your forage portion is good.
As far as supplies, I keep towels and iodine in a bin, that is pretty much it. Also good to HAVE, is a feeding syringe and colostrum replacer or heat treated frozen colostrum (or find a good raiser in your area you can call in an emergency). Even if you don't PLAN on bottle raising, ti's always good to have a couple of the lambar grey nipples (that fit on pop bottles too) on hand IN CASE.