This is one of those tips that keeps you from pulling your hair out. Sometimes when you’re editing values in a field (for example, you’re typing numbers in the Opacity field for a layer) and you’ve entered the number you want, Photoshop doesn’t automatically take you out of that field (meaning your cursor is still flashing in the Opacity field). It gets worse if you’ve switched to another layer (besides the Background layer) and you want to use a keyboard shortcut to switch tools. For example, you press the letter T to switch to the Type tool, but instead of getting the Type tool, you get an error sound because your cursor is still in the Opacity field (you can’t type letters in a number field). Here’s how to get around it. Just press the Return (PC: Enter) key on your keyboard to lock in the change in your field and release your keyboard for other tasks.