I found that blowing them out doesnt work well for me, i still have to let them dry for a few days after, and they get gunked up with residue from the water drying. And its a pain to blow out multiple cartos. I use the reverse taryn spin to dry my cartos.
taryn spin - YouTube
I use a empty pill bottle with a shoelace tied around the lip under the cap, with it I can dry several at a time. First spin i put the condoms on them to catch the water, after i just put a wad of paper towel in the pill bottle and spin it more. A good 3 or 4 spins and they should be dry enough to refill right away.
If anyone tries this with a lanyard or something to do one cart at a time, it helps to add some pennies to give it a little more weight. Spins much faster that way.