1. De-winterize your hall closet or mudroom. Take out all the winter ware, including hats, gloves, scarves, and boots. Store these small items in baskets or clear bins in an out of the way spot, such as at the top or back of the closet. Move bulky winter coats out too. Keep only what you'll use for the season easily accessible in your closet.
2. Find an easy spot to store summer essentials, such as sunscreen, insect repellent, and sunglasses, so you can grab and go. I use a hanging shoe bag on the back of my hall closet door. In the winter the many pockets are filled with hats and gloves, and in the summer, I switch them out to hold sunscreen, my daughter's sun hats, and sun glasses.
3. Clear the car clutter so you'll be ready for summer drives. Take a garbage bag out to your car and clean out any trash. Next, remove ice scrapers or other snow gear from the trunk. Replace this with a beach bag filled with sunscreen and beach towels, a picnic blanket, and if you have kids, don't forget to keep some beach toys handy for a last minute outings. If you are feeling really industrious, vacuum out your car and then wash the outside - or take a quick trip to the local car wash.  
4. Lighten up your clothing closet. Move winter items to the back of the closet or store in another spot, such as under your bed. Make sure to clean all clothing before you put it away, and have any wool sweaters dry cleaned to help prevent moth damage. If closet space is at a premium, consider storing off season clothes at a dry cleaner.

Now you've guaranteed that everything you need will be within easy reach - and summer should be all about ease!