you don't step up playing $5 a game, sorry, and you don't go in cold without watching and analyzing your potential opponents game.
You have to feel good about yiour game, every aspect of it, from breaking, shooting, kicking, jump shots, etc..
You pick someone that usually spots you the wild 8 ball, and play them even,
$100 a set. If you lose $2-300, you have learned a good lesson, that your game isn't as strong as you thought, so adjust your thinking when evaluating yourself, or yiou under evaluated your opponent, or both. This lesson may save you much more in the future. If you come out ahead, you have taken a small step up, and you are ready for some more. If you lose $100, you are close, but not quite there.
Now, if you are one of these guys that couldn't beat a real player without a brain transplant, then forget the whole thing. Referring to players that make the wrong decisions at the wrong time, and never learn a thing or two. Real good players don't want to gamble, they just want your money, and they usually are a percentage player.