IMPORTANT CAUTION: caffeine is a drug. it's not a controlled substance, it's not illegal, but it's still a drug. as with all drugs, don't try to prove your manhood by gobbling three grams (that would be near instant death in nearly everyone), and make sure that you always weigh it exactly to avoid overdoses. also, repeated use can be addictive (no studies to cite, just personal experience with withdrawal symptoms), and can cause insomnia (again, personal experience). don't use this in situations where you wouldn't drink two cups of coffee, because that's basically what's going on here.
Step 1: Quick Notes and Things You'll need
what you'll need (apart from readily available things):
itty bitty bottle
--(mine is a bottle from some candy flavoring, but any will do) - mine was .125 fl. oz, and it worked extremely well.
--(make sure it can read down to at least ten milligrams [.01 grams]. you'll want to be exact.)
--(note on caffeine powder: it's really not hard to get. it's not a controlled substance at all, and my brother got me 100 grams [1000 100-mg doses] for around 7 dollars. ebay would be a grand place to get it.)