You want to be able to create and modify actions so that you can turn out good looking work quickly.
Having a “toolkit” of useful actions (that you’ve made yourself) is a good thing.
For example, you’ll want a variety of actions for making distinctive-looking navigational buttons. Something to shoot for is an action where you set a selection, foreground and background colours, run the action and end up with a 3D-looking button. Bonus points if you include prompts for text-input to label the button, and have the action produce seperate mouseover states on different layers. Actions to produce scaled or set-sized thumbnails are often useful, too. That sort of stuff.
Getting used to using unique actions as a time saver is also something that you’ll need if you’re on the clock. A client has given you a CD with 100 source pics that need to be edited for the web? Don’t approach them one at a time. Do a quick overview and see if there’s anything that needs to be done across the board, and record that as an action. Run the action on a whole folder.
Actions kick ass.
If you’ll be editing photos, make sure you’re using the right selection method for each situation. A lot of people stick to one way of selecting pixels. (For example zooming right in and using the polygonal lasso tool for everything.) Before you select an area, find the easiest and most accurate way of targeting the pixels you want. If you’ve got a high-contrast background, the magnetic lasso tool will save you a ton of time. Remember you can target the areas you don’t want selected and then invert.
Alpha channels are often overlooked. I obsessively save alpha-channels when working with fiddly bits, and label them so they’re easily found. This saves a lot of time. Much faster to restore a selection you were working with before, and possibly modify it, than to spend time defining a selection from scratch.
Sorry if I’ve stated some obvious things here-- Photoshop is one of those tools that many people use quite a bit without ever really scratching the surface. (I was working with someone recently who called herself a Photoshop “master” – and a little observation revealed that she didn’t know how to apply or edit a mask. :smack: )