Don't despair. Think of it this way: If you only have a flathead screwdriver, you can only really effectively screw flathead screws. You'll need to add more tools to the toolbox to do any real work. Conning a sub is similar to that. Sometimes you'll use 4-bearing method, others you'll use periscope or deck gun, etc. It all depends on the situation.
I'd advise you to learn how to use the RAOBF wheel next (good tutorials on YouTube), also there is a thread
here with a few real good firing methods. Point is, you'll need to learn a few methods in order to deal with all the situations that you'll encounter. Best places to learn them is here and YouTube.
Some of them can go really deep, geometry, trig, or just good plain old map work.