This is a season synonymous with cleaning, so you know your desk is one of the first things you should be tackling.
Clear your desk and take stock of everything you have. And while you're at it, brush away the dust that's been collecting on the items on your desk and wipe them down with some sterilized wipes. Sort the items by type and either throw away or recycle the ones you don't need, or file them away in a special spot. For more tips on organizing, read this.