Soaking Dry-Packaged Beans  Before cooking, soak dry-packaged beans to help soften and return moisture to the beans and reduce cooking time. Most beans will rehydrate to triple their dry size, so be sure to start with a large enough pot.

• Preferred Hot Soak and Quick Soak Methods -- Hot soaking helps dissolve some of the gas-causing substances, making the beans easier to digest. For each pound beans, add 10 cups hot water; heat to boiling and let boil 2 to 3 minutes. Remove from heat, cover and set aside for at least one hour (Quick Soak), or up to 4 hours (Hot Soak).
• Traditional Overnight Soak -- For each pound (2 cups) dry-packaged beans, add 10 cups cold water and let soak overnight, or at least 8 hours.

Cooking Dry-Packaged Beans

• Drain soaking water and rinse beans; cook in fresh water. In general, beans take 30 minutes to 2 hours to cook depending on variety. Check bean packaging for specific cooking times and instructions.
• Spice up beans while they cook. Seasonings such as garlic, onion, oregano, parsley or thyme can be added to the pot while beans are cooking.
• Add acidic ingredients, such as tomatoes, vinegar, wine or citrus juices, only at end of cooking, when the beans are tender.
• Add salt only after beans are cooked to tender. If added before, salt may cause bean skins to become impermeable, halting the tenderizing process.
• To test for doneness, bite-taste a few beans. They should be tender, but not overcooked.
• When cooling, keep beans in cooking liquid to prevent them from drying out. 

From http://www.americanbean.org