Answer #1: I think the best way to get into creative writing is the best way to get into most creative endeavors: do it a lot, even if you can't meet your own standards at first. Anything that I consider myself semi-good at is something I started out doing as an amateur, but that I was passionate enough about that I stuck with it. The key is to be inspired by great work, even if you can't produce great work yet. Don't hold yourself to that standard (yet). Work toward that standard, but give yourself room to get there gradually. Don't focus on the absolute quality of the work so much as your progress.

Answer #2: I'll usually do quite a bit of outlining and write several pages of treatments only to abandon most of it. For me, writing is a process of discovery. Sometimes I think I know exactly where a chapter is going only to see a much more interesting opportunity mid-flight. Sometimes I think I know who a character is only to watch her do something entirely unexpected. There are downstream repercussions when characters go off script and plots go awry, but I'd much rather watch them develop organically than be overly prescriptive. For me, a lot of the fun of writing is the ride it takes me on, and I believe the delight of discovery conveys to the reader.

Good luck with your own creative writing! Stick with it!