Hey, OZAB. I'm a newbie here, too, but have got back into this after some time off, but I thought I'd offer a few elementary things that maybe helpful to you. All the advice here is spot on, you can only get better listening to these guys. If I could offer my own thoughts, it would be this. Rule #1, thin your paint (like skim milk) and blot your brush. Take time to carefullyprep the figure, very important. The best paint job in the world won't hide mould lines. Go get yourself Walmart flat white spray paint (pic) for primer, and get lots of it because you'll need it. At 96 cents a can, you have no business spending $14 on a can of the GW stuff as a newbie, or a pro, because it's simply better. Try it and you'll see. Get a big bottle of Simple green, or Mean Green (pic), again at Walmart, $4 bucks. You'll need this for stripping figures after each attempt at painting it. Get an old plastic container with a lid for an overnight soak, scrub with an old toothbrush, dry, prime, and paint it again, and again, and after that, try again. You simply will get better. That being said, try and stick to white metal for a while, plastic won't last after multiple strips. Get a loupe (pic) $10, ebay, and you'll literately see figures like never before. Buy good brushes and keep them clean. Unless you're really good at doing eyes with a brush, save yourself a lot of frustration and use 005 Sakura Pigma Micron pens. $10 on eBay for an assorted color pack. Don't drybrush. Ever.
Buy some figures you wouldn't normally try from time to time, and don't underestimate the importance of that, trust me. Don't expect instant results and you'll be less and less disappointed. As incredible as the minis on here can be, which can be so damn good it's also discouraging, remember that you're better now than they were at some point in time. Just enjoy it, learn and practice, and it will come to you.