Step 3: Start Working On Your Project
Use a color that will represent that section of your project your tools fit. Whenever you need to work on this section again, you'll know exactly which wrenches to choose, even if they're mixed up with all the others.
Do the same with every other component. If one size is used in more than one area and you have spare wrenches, you can paint each a different color. If you don't have spares, then you can paint a single wrench multiple colors. Neatness doesn't count.
The key is, paint the wrench to mate with the job and forget about size.