My DIY project for June was to make a Swimmer's Ear solution. Fortunately, we've done a lot of swimming, but haven't had any problems so far. I'm pleasantly surprised that we haven't had to use this, but in case you're in need of some ideas. Here's what we came up with:
DIY Swimmer's Ear Solution
1 part alcohol
1 part vinegar
Mix together well and put in a dropper bottle.
Place 2-4 drops in the ear after swimming.
I've seen ideas where it's been stored in a contact bottle or medicine bottle with a dropper.
I also have a friend who soaks a cotton ball and places it in her son's ear.