Man I’m only getting this now I’m so sorry! Apparently the phone version of tumblr doesn’t alert you when you get ask anythings?!
So for stuff that’s useful for getting into UI/UX… It’s really just about showing in your portfolio that you’re capable of iterating and thinking your way through all sorts of problems. Some useful assignments that I think would be good for a portfolio piece would be to redesign the UI of a couple of your favorite games. Come up with alternate solutions to elements that you find in the game and more importantly explain why you feel that would be a better solution. Come up with multiple solutions. Show that you don’t marry yourself to one and that you can think your way through a problem from different angles not just get stuck on one path.
Aesthetics follow the functionality part. In UI design like in most types of design, the functionality is the part that needs the most attention, and needs to be nailed down first. However aesthetics are still very important and different types of games call for different types of visuals. A sci fi game can get away with glowy UI (see Destiny for a good example of some real slick sci fi UI in next gen) Whereas games like The Last of Us would feel a little weird with glowy techy elements on the screen. Likewise, The Last of Us’ stark minimal elements would probably feel a bit out of place in a Zelda game. Find a few companies you’re interested in applying to and familiarize yourself with their aesthetic. When you do apply, make sure you’re putting the stuff that’s relevant to their style at the top and any other stuff towards the bottom.
Another thing to keep in mind is that many mobile studios and start ups will hire you just based on a good graphic design portfolio. You can get in that way as a graphic artist or a UI artist minus the design part and start working towards involving yourself more in the design portion. That’s how I did it. I started as a “graphic artist” at HB studios in Halifax, Nova Scotia. I just did the little graphic elements that my lead asked me to do, I wasn’t involved in functionality. I learned a lot about the process of design from that job which I was able to bring with me to the next job. I learned stuff from that job and brought it to the next and so on and so on till Naughty Dog :)
For books and things you can pick up, one that I constantly find myself coming back to when I’m stuck is this one: http://www.amazon.com/Universal-Principles-Design-Revised-Updated/dp/1592535879/ref=sr_1_1?s=books&ie=UTF8&qid=1403286078&sr=1-1&keywords=universal+principles+of+design it’s a great reference book that I’ll skim through when I’m stuck on a problem or when I’m stuck on a certain way of thinking about a problem.
I hope this helped a little? If anything was unclear or if you need more information just ask!