1.) First, rip or cut two 1"x1" squares of aluminum foil. Wrap them around the two ends of the battery tightly to ensure a good connection. Make sure that the two pieces of aluminum foil DO NOT TOUCH! Trim down the aluminum foil if appropriate.
2.) Next, stretch the 1"x1/4" rubber band around the battery and over the positive and negative ends. If the rubber band isn't centered over each end, realign it. The aluminum foil should now be held firmly in place.
3.) Lastly, strip the ends off of two pieces of 2" 20 gauge wire (it is handy to have different colors, but not essential). Insert one of the wires under the rubber band and into the aluminum foil. Repeat this process on the other wire. It doesn't matter if the wires don't touch the positive and negative contacts on the battery, so long as they are touching the square of aluminum foil.
Your battery holder is complete. To test it, try hooking it up to a light bulb or a low-voltage LED and resistor. This little AA battery holder will make it easy to hook up and test your inventions and experiments. With only a few common supplies and 5 minutes you have a simple AA battery holder with loads of possibilities.