Adjustment layers

You can edit all the frames in your GIF at once by using adjustment layers. Adjustment layers give you all the classic edits like levels, hue/saturation, color balance, exposure, etc, in a convenient layer that sits on top and affects all the layers below it. Look right above your layers palette for the menu that looks like this, full of symbols:

Run your mouse over each one to see what that icon represents. MAKE SURE YOUR LAYERS ARE ALL TURNED ON. Check your "little eyeballs" on each layer. The adjustment won't take effect in a frame of your animation if that layer is turned off.

****Don't forget to resize your GIF****

1. Click   Image--> Image size
2. Change "pixels" to "percent"
3. Enter a suitable percentage size (Hint: What size are you viewing at in Photoshop??)
4. Click OK