Currently working on subfolders for the different sounds (i.e. tonal kicks/top kicks/punchy kicks), and organizing my foley and SFX folders.
Not pictured: acapellas folder (needs organizing), personal foley files and other field recordings, stems from remix comps and other places, and my slowly developing personal "sample pack".
As far as how to organize your samples, here's how I went: I made a whole bunch of folders and subfolders (similar to picture), and I opened two finder/explorer windows - one with all my purchased samples, one with my new organized folder system. I listened through and started dividing everything into its proper place. Took me like 3-4 hours, and it's really tedious, but it helps a lot. From there, you can start further subdividing the samples so you can just find them ASAP, deleting samples that seem to just clog up your library (i'd personally move them to a "Trash Bin" on an external hard drive just for archiving but it's all up to you), and eventually finding the sounds you really like and putting a duplicate into your own favorite samples folder.
