Wet a paper towel. Squeeze most of the water out.
Fold the paper towel to fit into the Ziploc bag. Place in the bag.
Insert one or two pinto beans per bag on between the paper towel and the side of the bag. Do not seal the bag.
Tap a nail into the wall on each side of a bright, sunny window. Stretch a piece of twine across the window, tying it to the nails.
Hang the Ziploc bags on the twine with a clothespin with the bean facing the window.
Monitor the Ziploc bag, making sure that the paper towel stays moist while the pinto bean sprouts. Pinto beans germinate quickly, sometimes overnight.
Plant the bean sprout in a paper cup with potting soil or in the garden. Handle the root gently. It breaks easily. Water the sprout thoroughly after planting.