Now that I've been working with Lightroom for a while, I've learned a few things. I don't use Collections. My folder system is such that Collections are only duplicate effort, that's wasted. I spent a lot of time setting up collections. It helped me learn how to move photos around in Lightroom, but aside from that, it wasn't worth it.
I've learned how to import and rename photos and get them into folders on my hard drive. Lightroom does this well. It took a couple of oopsies, with photos landing inside folders that I didn't expect them to be inside before I learned how to determine where they will go.
Before I had Lightroom, renaming photos was difficult. Now I always rename and sequence my photos, giving them a name and a number. It is much easier working with '2-18-2011 Josh Birthday-7.jpg', than it is to work with 'DSC_0926.jpg'.
I've added a step to my import process. Immediately after I import, I go through quickly and delete the duds. The exposure tests, the flash failures, the ones where someone sneezed. You know. This reduces the total number of photos I save. It also makes me look like a more competent photographer. I have fewer duds.
Looking through my photos like that has also cued me in to some of the errors that I make when framing up photos in my camera and has made me decrease the frequency of that error. The first step in correcting something is to recognize that it needs correcting.