I think I'm the most unorganised person ever.
For CT's I have a folder for each one and put the kids in them, once I've used a kit they go into a sub folder called used within each one.
For bought kits I have a folder called 'Bought' and they all go in there, once a month I put them on my EHD if they've been used and I have a folder for each SSD designer on that then each kit goes in the right folder!
That's it, no tagging etc for me!