Here's what I've got going:
The two taller containers hold the actual cleaning chemicals. One of them is for stuff I'll only use for a full detail bi-anually (clay stuff, polishes, sealants, pads, etc.) and the other for stuff I'll use on a weekly/monthly basis (car shampoo, wheel cleaner, interior cleaner, leather stuff, etc.). Of the two smaller containers, the top one holds tools and equipment (brushes, foam cannon, fire nozzle, bug & tar sponge, etc.) and the bottom one hold all my MF stuff. The MF is further separated into Ziploc bags, on which I've written what kind of cloth is inside, and what it's used for (so what's on it, if I haven't cleaned it recently). Oh, and the bag is where my UDM lives.
Everything hangs out in a kitchen cupboard when not in use. One of the advantages of having more cupboards than a 20-something bachelor really needs to store food in.
Yes, I do have a touch of OCD.