The biggest tip I can give you is to truly evaluate everything you have and get rid of things you don't need. If you don't use it for three months (barring seasonal items), you don't need it. For seasonal items, if you don't use it for a whole season it's intended for, you don't need it. Having too much "stuff" takes up a ton of time, space and money as we try to organize it, clean it and store it.
In your closet, take everything on a hanger and put it on the rack with the end of the hook facing toward you. After that, anything you actually wear gets put back with the hanger pointed toward the wall. After a few months, anything with the hanger still pointing to you goes to Goodwill.
For kitchen, dresser drawers and bathroom, take everything out of them and put them in a box in another room (you can work on one area at a time). If you need something, get it out of the box and, when finished using it, put it back in the cabinet/drawer. Anything still in the box after a few months goes to Goodwill.
Keeping something because of the memories? Consider taking a picture of yourself with the item and donating it. The picture will help you recall the memories just as well as the item itself and take up less space, while letting someone else benefit from the item.
Nick-nacks? Next time you dust, ask yourself if you really love the item well enough to continue dusting it. If not, donate it.
Do all of this and you'll be pleasantly surprised at how much time and energy you save trying to keep everything organized by simply not having it. You may not feel the money part readily (unless you're getting rid of stuff in a paid storage unit), but you are saving there, too.
Have fun!
