There are lots of ways to do this. Kodak makes some really first class films and emulsions, as do Ilford and Fuji. They are treated to be highly resistant to damage during processing. The way I do it is that I take the edge of a rubber windshield wiper, make sure there is absolutely nothing harmful trapped on the blade edge, dip it in wetting agent (PhotoFlo), and gently run it along the entire length of the film. Both sides. Even the emulsion side. I have never had a scratch using this technique, and have used the same wiper blade edge for roughly 1,000 rolls of film. Not a spot on the negs either. I use Sprint 'End of Run' wetting agent, by the way, but I'm sure PhotoFlo works just as well or better.
Thanks for the kind words!