What are some pinball skills a beginner could learn to improve his/her game?
Watch other players. https://dmvpinballs.shop I think I got more out of watching John Norris play Mata Hari for 5 minutes than I would get from a year of practice. This has a limit, of course, but it can open up logjams of skills you can't start developing without having seen them in use.
Try and catch the ball(s) each time. Really. Your odds go up big time vs. just flipping the ball back. At least for me, I probably have way more fun not catching the ball and I have to discipline myself else I revert back to 'reactive' playing.
Don't restart the game when the first ball(s) are losers. This does something to your psyche.
Breathe. I think sometimes I forget and I subconsciously will want to lose the ball because it is then that I take a breath.
