Things You'll Need
Instructions
Research your card game. Use a guide for your trading card game or search the Internet to find information about how rare specific cards are and how cards tend to be distributed in booster packs.
Calculate the odds of finding a rare card in a booster pack. Take into account what kind of booster pack it is and how frequently rare cards tend to show up in that particular kind of booster pack. For example, in a series of booster packs that generally contains one "rare" card for every 12 "common" cards and 10 cards in each booster pack, you'll want to buy at least two booster packs to match these odds.
Purchase booster packs. If you do not already have some, purchase one or more booster packs at a trading card game or other store.
Open the booster packs. Review the cards and look them up in your card guide to determine each one's rarity.