There are so may ways of making it. The one I am using now is:
4-TBLS alcohol
1 1/2-TBLS castor oil
1 1/2-TBLS witch hazel
1/2-cup water- or in the winter- window washer fluid
I just started using this. I got it from another forum, and so far the clean up is the fastest I have ever seen.
I also have used Ballistol, Murphys oil soap, and water, with good luck.
I use something that is called "MOOSE SNOT" for hunting. It is:
2-oz of beeswax
8-oz of castor oil
1-oz of Murphys
This also makes clean up at the end of the day, very quick.