My garage is a mess and yours probably is too. Now I periodically clean my garage as you may, but it gets messed up eventually due to my kids, wife, as well as me. I’ve gotten pretty good as cleaning it up and here are some tips on what works very well.
You are going to need an open space to work in. This could be floor space in the garage, perhaps table space, or even outside in the driveway. You’ll need this space to help sort things. My favorite way to create a sorting space is too get rid of larger unneeded items, perhaps via Craigslist or Freecycle.
The biggest stuff is the easiest to deal with. No doubt you have some large items you can sell or otherwise get rid of. Projects you may never get to are prime examples!My garage like yours probably has seasonal items, like snow shovels, spring time planting equipments and more. Organize these items seasonally for easy access, while getting rid of duplicates and unnecessary items. The seasonal items can often be filed in the less accessible areas.
You also need some sort of organization system for other items so that you can use space effectively as well as find what you want easily. This may involve building shelves or getting other types of organizational items like hangers, etc. Wandering through the hardware store or a friends garage can give you ideas.
Remember to eliminate and organize, and do it regularly. This is the only way to keep your garage clean and functional!