I know this is a joke, but if you really want to improve your character play, I highly suggest taking a full week, spending 20 -30 mins a day roleplaying to imagined scenarios, replying to them out loud.
As most actors can tell you, if you want to nail down a character all you need is practice, once you gain that confidence you'll be the most interesting character at the table
Look you interpret however you feel will best help your mental health