CHANGE ONE PREFERENCE, SAVE A BUNDLE

If you're creating Web graphics with Photoshop and you're not using the Save for Web feature (which is perfectly fine not to do), make sure you go under the Photoshop menu (in Mac OS X), under Preferences, and choose File Handling (in Windows, Preferences can be found under the Edit menu). In the Image Previews pop-up, change the setting from Always Save to Never Save. Image Previews are those tiny thumbnail icons that are visible on your system. They look cute, but they take up big space often accounting for 70% of your file size. Turn them off, and you'll save file size big time. (Save for Web does this automatically, so if you're using that feature, don't sweat it.)