How to make chocolate covered strawberries?

I have semisweet and milk chocolate morsels. I’ll probably use both, separately.

Do I just heat the chocolate (double-boiler style) and dip, or do I need to add more ingredients to make the chocolate harden properly?

I’ve seen some recipes that use Crisco (which I don’t have) and some that use butter (which I do have). Some warn ”absolutely no oil!!1!!” and some specifically recommend it.

So… what works for you?