use photoshop =] and download the templates from master skinnerz forgot the site >.<... their templates are 2048x2048 by default =] and if you're gonna get objects from somewhere make sure they're pretty big as well so start big and size them down =] the decals i used for the XRT_shikelite skin was twice the size of the skin itself lol and i just sized it down so its more high res.. hope that helps in your next skin =D
lol dont doubt yourself so much, it takes time to get used to it, ive made about 8 skins now and they are all really bad, but each one I do I learn a new thing that helps with the next skin.
And remember, its better to try than not try at all. Keep going, youre doing great.
The res thing gets me a bit, especially when LFS resizes it to 512 x 512 some of my skins just become a blob of pixels.