You can actually overdo it (been there done that). You don't need to completely saturate the cotton, just get some worked into the outer layers. When in use, you can peel them open a bit and give them a spark. Don't expect a signal flare, just a nice little flame to get the bigger tinder going.
They are like Velveeta and Twinkies— they will outlast all of us :) Film cans work nice for stashing them. When you are looking for plastic vials to decant stuff into, keep an eye out for one with slightly larger openings— great for cotton balls.
Another cotton ball trick is to put them in duct tape. The tape will burn too. Slice the tape open, pull out some cotton and light it up.
Some folk jam them into soda straws and then fold the ends over and melt them closed.
You can use cotton balls and alcohol gel hand cleaner too– takes off with one spark. Make sure you don't have gel on your hands when you light them– you'll do a Young Frankenstein act— Fiiirrre!