in general, I would recommend that you set up a lab of systems (or virtual systems) at your home or a location that you can access in order to test the tools and procedures that you learn in class. being able to reproduce your exploits in a controlled environment will most likely give you a deeper understanding of what is going on here.
do everything from class again, but at your own pace so that you can fully understand what is happening.
do not gloss over the documentation and procedural processes of the job. they are more important than the sexy part of attempting your exploits. build a strong procedural base first.
remember, if it isn't documented, it didn't happen.
start paying attention to as many credible resources (blogs, et. al.) as you can find. Read them every day.
become involved in the community and try to understand all the tutorials and feedback that you can get (not only here but in other locations).
start reading A LOT. I would start with "Professional Penetration Testing: Creating and operating a formal hacking lab" by Thomas Wilhelm. Do the exercises, then do them again.
ask if you are confused... but do your home work first.
stay within your integrity at all times. the days of corporations hiring "reformed" black hats is all but extinct.
keep pictures of your family around so that you can remember what they look like...
good luck with that!