What you'll need:
brown paper lunch bags
Fold flattened paper bag lengthwise and punch holes along one long edge, approximately 1 inch apart, punching through multiple layers at one time. Flip the bag over and punch along opposite side. Open the bag, insert onions, garlic, or shallots; fill the bag up to half full. Fold top of bag over 2-03 times, label the top with a marker, and use a paper clip to hold the top in place. Store filled bags in a cool, dark place, so that air can circulate between the bags.
Remember: No plastic bags. That only accelerates sprouting and spoilage because of the lack of air circulation.
Another reminder: No Potatoes nearby. Potatoes and onions should not be stored together. They give off gases that will accelerate spoilage of each other.