Hi. I'm not experienced modeler either having done only 1/400 academy Titanic and currently working with 1/700 Olympic from revell. I don't know which way is considered to be the "correct" way but I've removed the masking tape immediately after painting. Perhaps that way your paint will not get of while removing the tape. What I've also done is that I've used a very sharp knife to carefully scratch of the paint which have leaked into wrong places. It has worked surprisingly well. Remember also that painting is something you shouldn't be afraid of, because you can always put a new layer of paint if you have "messed up" something.
Good luck with the build and welcome to the forum!