i'm 31 and i only started building last november, i've gotten so much better in that time (mainly thanks to the people on this forum) It's really noticable when looking back over my builds. I just kept at it and learned gradually, I think trying 1 or 2 new skills on each build worked best for me, I tried far too hard to do too much on one of my early builds and it ended up looking worse than my very first ! I am still mainly focusing on making my builds clean and my paint even.
I have recently stepped up with painting but still have a long way to go to get to the level of some of the guys on here, but for me thats part of the fun.
Just stick with it and don't expect perfection for now. look at every mistake as a lesson learned and view each build as a slight progression.
as for painting I find gradually building up light coats and lots of sanding to be the best method. Practice on some other stuff to help your technique too, I paint allsorts from Broken playstation controllers to plastic tubs/boxes !