I am getting a new computer and going through a huge decluttering process with all my files. I am not the most organized person, so having processes in place to help are so valuable. I've even gone back to the early days--pre-lightroom. I thought it helpful to share my recent thoughts.
TIP No. 1: You don't have to rethink your entire photo library and previous files to start using lightroom. that would have been overwhelming for me too. Just start fresh going forward. I've only recently imported all of my old files into my lightroom catalogue--4 years later.
TIP No. 2.: if its an image you really care about save the raw file. I hope by now I've convinced you about the importance of shooting in raw. If you aren't shooting in raw: Save the original jpg. Back in about 2005 my skills along with the capabilities of the software were way less than they are today. It's nice to know I can go back and rework, if I want to. (most likely I won't, but reassuring to know I could)
TIP No. 3: Raw files take up so much less space than psd files. When going back to clean out my pre-lightroom and pre-aperture days I almost always threw away the psd file. Why? I did a lot of work on some of those images in ps. But the programs today do so much more. I'm not sure how much I care about the image now. But also not sure I want to throw it away. Easier to remove 40mbs than 8. Unless I've done a huge amount of work to the file, but that's not the bulk of my images. Even then I might flatten it and save as a high res jpg. and still keep the raw.
Also, many of those changes can easily be done in lightroom today with the raw file. So I have one file (and a significantly smaller file) to archive instead of 2.
TIP No. 4: Keywords. This is less of an issue if you are already overwhelmed, but it is so helpful if you can do this for new files upon import. I keyword the location, and other facts with each import, so if I search in lightroom for a person or a subject that I know I photographed but don't remember when, I can type the keywords and all photos with that search term will show up.
Hope this is helpful and happy shooting!