Here's a good method to practice.

Organization doesn't just happen - it's a result of conscious actions.

1. Start by tackling a particular room armed with a trash bag, a giveaway box, a box for items you want to sell and a box for things that belong in another room or your home.  Make quick, unemotional decisions: if it's broken, obsolete or redundant, get rid of it.

2. Sort through all the items that will stay in the room, matching like with like.  Cluster books together with other books, DVDs with DVDs and outerwear with outerwear.  Don't comingle dissimilar things - it makes it hard to find what you need and creates visual chaos.

3. Take inventory of what you're holding on to, then determine how the items should be stored and what types of furniture and containers you'll need.  For example, to keep stacks of sweaters and T-shirts separate, you can use shelf dividers.  Now that you've counted your CDs, you know you need a CD organizer with 8 shelves.

4. Find solutions that work with your personal habits.  For example, if you're a no-fuss type, just grouping things together might be enough, so store pictures in photo boxes marked by year.  If you are more detail focused, use photo albums.

5. Don't stop until every object or type of object has a place where it lives all the time - be it a tray on your desk for your cell phone or a hook for your keys.  Then, commit to returning each item to its home after every use.  Soon, putting items away will become a habit.