You can’t get good at it if you don’t do it. There is no other way to learn it. It’s always best to start with a head (or two) that are junk so you can learn how to get the shape you want.
I don’t use stones for porting very often. I use carbide burrs. You need to be able to control cutter speed.
There are plenty of threads on here about porting that are worth reading. There is no substitute for time behind the grinder.
