When it comes to spirits, the higher the proof the better - if you have access to Everclear (Clear Springs, Moonshine, etc.) or overproof (151 proof) spirits they will work the best. Otherwise, I would recommend using 99% Isopropyl Alcohol. I would recommend picking up a medicine dropper, as it will allow you to ensure you don't get any of your chosen spirit on the finish (potentially causing damage).
Some people use salt, however, I find that simply filling your bowl with a cotton-ball or two works, and doesn't leave as much of a mess to deal with. If you go with salt, I've heard that rock salt is the way to go over kosher; couldn't tell you why, it's just what I've heard - either way, I would avoid anything iodized. I also like to stick a fluffy pipe-cleaner down the shank when I'm performing an alcohol cleaning, I am always surprised at how much gunk it picks up.