1 part apple cider vinegar to 1 part water.
the vinegar smell goes away when it dries.
this is also an instant soother for ant bites.
the only time we've been able to play outside has been in the evenings due to the heat, and this has kept the swarms of mosquitoes at bay. no more stinky insect repellent!
(and the candles just don't work for us)