Your garage is no doubt a dumping ground for a myriad of unmade decisions. "What do we do with ...?" "I don't know. Put it in the garage." Items sit there like orphans waiting to be adoped. Valuable real estate is lost. The car lives on the street.
Stop the madness.
Cull through your treasures and toss, donate and recycle with realistic abandon.
Make categories of the items you wish to keep.
Decide if they need to be boxed (seasonal decorations) or kept out because they will be used up quickly (paper products from a big box store.)
This elegant example comes from The Container Store and it's pricey. You can get a down and dirty version at a place like the Home Depot. The more expensive version can be moved inside because of its good looks. Take the long life of your purchases into consideration. Very often we only focus on saving money and lose out on versatility.
If you rent and don't want to put in an expensive built in system shelving is the way to go. It's portable. It will keep things off the floor. In the event of a flood you'll be so grateful. And besides who wants to open a garage door and see things strewn about like forgotten tops the day after Christmas?
Warm weather is coming. Schedule a few purge days on your calendar.