Unbend a paper clip with your hands until it is straight.
Take one metal clip off of a binder holder. Binder holders are usually black and have two metal clips on top that you squeeze to open it. Squeeze together the bottom of one of the silver prongs to remove it from the holder.
Straighten the binder clip top by separating the ends and pulling them apart.
Hold the binder clip in one hand. Hold the straightened paper clip in the other.
Push the binder clip into the center of the lock. Do this firmly and in one motion. Hold it steady. Push the paper clip just beneath the binder clip. Hold this steady as well.
Turn the two clips counterclockwise together slowly until you hear the lock open. If it is a small lock you may not hear it. If the lock is not completely open, insert the clips again and turn it more.
Use a little silicone spray lubricant if the drawer is old or the lock is rusty. Insert the nozzle into the front of the lock and spray a little. That should loosen the lock's movement or remove any buildup of dirt or rust. Try to open again by repeating the steps above.