Weirdly enough for me using a vibrator made me better at getting of with my fingers. I used a hitachi magic wand and it works so well that I honestly didn’t need to fantasize or even be very turned on in order to cum. I didn’t realize until after I started using it that most of what was holding me back was a mental block... you have to get totally lost inside your head with arousal in order to have an orgasm (wether you’re masturbating or with a partner— I know this probably seems super obvious but I didn’t realize it was holding me back). Once I got comfortable with being able to let myself fantasize without feeling bad I was able to get off in a couple minutes using my fingers every time. It was a complete 180. As far as the rest goes, I would say using a quick, repetitive motion on the clit is good and it’s bit different for everyone. Also, even if you already get pretty wet using lube on top of that can’t hurt and will probably speed things up a bit.