Few things in this world are as useful as a good stick. Find one each time that you go out, especially if you're going to be wading.
Be flexible and innovative. Always be ready to change your way of thinking.
Be friendly to your fellow fishermen, they may know something that you don't and, more importantly, they might be willing to share.
Learn three knots inside out. Tie them daily (and never forget to wet a knot before you snug it up). It doesn't matter which three, as long as you can tie them in your sleep and they can do the following: tie on a hook, connect two lines together, create a dropper loop. You don't need to be a knot god, but make those three knots work for you.
Respect yourself and your environment. Don't leave crap lying around.