Before you begin adding all the places to store your tools, decorate your garage space. Your workshop is your space. Whether it's a simple coat of paint on the walls in a bold color, a checkboard floor or metal on the walls decorate it to fit you and the types of projects you do in it. If you love cars, put up old car signs. If you're a woodworker, create a custom cabinet for paints and stains.
If your workshop space functions as both a workshop and a storage space for your cars, keep the items in your shop moving. Install wheels with brakes that lock into place on your benches and tables, if you can, so you can push them aside when you have to make space for the car. Use heavy duty, strong caster wheels to keep the wheels from breaking. When choosing a type of wheel, keep in mind what you plan to use your tables for, so you can plan for additional weight.
For a quick weekend do-it-yourself project, organize your space. Purchase or make shelves to line the walls. Install pegboard or hooks to hang tools and other items. Buy a locker, drawers or other organizational elements to store tools, paint and other items. If you have unused ceiling space, use that too. If the joists are close enough together, store lumber in the space, or spend the weekend adding a floor to create a small attic space where you can store items you don't use very often, like household paint or outdoor holiday decorations.