Discardia isn't just about things. You can build up too much of intangible stuff you don't need as well. Personally I've found that it's harder to get my head clear when my house is a chaotic mess, but if you need to tackle the head first, just go for a walk and get yourself somewhere you can sit and think for a bit.
I recommend the beach, but a hillside, park or quiet corner at the museum can do the job as well. Go where you won't hear other people's conversations or see any advertisments.
Sit and be still.
Pull yourself out of your head and into a quiet space.
Then, when you've slowed yourself down and gotten out of your workaday brainrace, take a look at what's taking up your mental space.
Are you angry? What needs to happen for you to let go of that upset feeling?
Anger burns up an enormous amount of energy. If something was wrong, why should it deserve one more minute of your time? Write a letter, schedule some counseling, forgive someone or yourself, but let it go and move on.
Are you sad? Depressed?
That's a tough space to get out of. You can't just "make happy" or let that one go so easily. There are some good techniques to loosen depression's hold on you. Get active. Every day spend at least half an hour walking or gardening and being aware of your surroundings. Get involved. Do something regularly to help other people. Volunteer once a month at a soup kitchen or the library. Help a senior or ill person in your neighborhood with errands or groceries. Get aware of the good times. Keep a journal and be sure to write in it when times are good as well as when they're bad. Depression can make it seem like things will be bad from here on out, but depression is a liar and it helps to be able to see your cycles.
Are you worried and fretful?
Watch out for worrying about multiple incompatible outcomes and thinking you'll have to have the strength to weather them all. Remember that the best way to get yourself through future hardship is not to make yourself a wreck right now. For each worry, find one small tangible thing you can do to make it less likely or less harmful should it become real. Remember you don't have to solve everything all at once. A step in the right direction is a good thing and better than being a deer in the headlights.
Are you bored and lethargic?
Sometimes it's a retreat from stress elsewhere in your life, sometimes it's frustration causing you to give up and be a lump, but boredom is definitely a trap you build yourself and it can be the easiest to escape. The cure is to stop doing that kind of doing nothing where your mind isn't still. Turn off the television. Cover it up and pretend you don't have one. Don't turn on the computer if your form of ennui involves mindless surfing and evenings lost to unsatisfying chats. Make something. Write a letter, you know, on paper. Go spend time with someone old. Ask them to tell you about their favorite things to do when they were in their teens. Learn to cook. Reconnect with one old friend every day for a week. Just keep yourself from wasting time in the unfulfilling ways that have become a habit and remember that you have good options.
What else fills your head that you're ready to part with? How can you sweep it out the door and get on with the good stuff?
Carry on in the comments with more thoughts and ideas, please.