Eq is a liquid, so basically, you just mix it with whatever oil you are going to use.....then just add a small amount of BA for bacteriostatic purposes.
Test Enanthate has a low melting point, and is also easily soluble, so you just add it to your oil, warm it up, and add a small amount of BA for the bacteriostatic purposes.
Something like Test Prop, or test no ester, is a lot less soluble, so you need the additional co-solvents to help keep it in solution.