First and foremost, you must pick good quality bananas. Although they are green, you can determine based on size and look which bananas appear to be healthier than others. Try to find bananas that are not damaged in any way and that are medium sized. Although they are green right now, make sure that the texture of their skin is smooth and without any flaws. Ask your grocer to help you find the best bananas that are the freshest in his or her stock.
Place either a bunch or a collection of single bananas into a brown paper bag. Add an apple into the bag as well. Apples as well as bananas themselves release ethylene, which aids surrounding fruit in ripening. Poke a few holes into the brown bag and seal the top by folding over a few times. Take your time while doing this as you do not want to squish the bananas because you are rushing to get this done.
Wait and Check
Place the bag in a cool, dark and dry place to allow the ripening to occur. Check on the bananas every 2 days to ensure they are coming along well. Do so until individual bananas or the whole bunch appear and feel ripe. Remember you check the bananas frequently. Once you see that they are starting to ripen then take them out of the brown paper bag and place them in your usual fruit plate or basket.
Once ripe or almost ripe, feel free to allow the bananas to ripen further in your fruit bowl or counter top. The bananas should either be ready or will soon be ready to be eaten and enjoyed, so go ahead and do so. Remember that you can repeat these steps with any bananas that you buy in the future. Just make sure that the paper bag is big enough to handle all of the bananas without damaging them.