Jury-Rigging a hose/spigot

So I just opened up a small rental car place and there is no running water. It sucks but life goes on and I do what I do best, jury rig stuff. Now I have the basic principle but I need some help implementing it. I want to create a hose/spigot from a 55 gallon drum. I have my air compressor with the standard 1/4' attachment. Obviously beer tubing, that will run down to the bottom of the barrell and that will be connected to some sort of barb on the underside of one of the barrel caps. On the other cap I will put the air in chuck.

Question is in the fittings. What do I need to create the sprayer/hose conversion for the liquid spout and what fittings do I need for the air in side.