1. Think like smash bros in terms of dodging and landing on the ground after being kicked by pressing L.
2. In terms of aiming, think like mouse and keyboard instead of console controls.
3. Get a weapon that suits your taste, there are like 100 to choose from. Personally I like one with rapid fire, high knockback and lots of defense, like a +6 defense ball cannon.
4. Play on highest difficulty, feel your toes curl inwards.
It does indeed take a while to get into it, and even then it ends up not being a game for everyone. But give my advice a try.