Also, as a guy who started using GIMP over a couple years ago and now only uses it, don't underestimate the power of just playing around. Tutorials are great; they give you an idea of what people before you have done. But be sure to look around the menus, the various options on the filters, and all the tools in the toolbar. Don't know what something does? Run it and see! It'll also help you bridge the gap between 2.6 and 2.8 tutorials: sometimes the same feature will be in a different location, or there'll be a similar feature that you can substitute in.