Well, aluminum won't rust so you must be talking about the bolts or cap screws that hold things together. Frankly I don't worry about them too much. Short of coating them with clear laquer or something they are going to rust if they get wet. It doesn't hurt anything.

If it's a target bow and you want it pretty then stay out of the rain or tear the bow down after shooting in the rain and clean all the bolts up. If it's a hunting rig then, oh well.........