What is the best way for a college freshman to learn enough about UX design to be valuable to a startup in 3 years?
First, don't call it "UX Design". Call it Product Design. You'll earn far more credibility by calling it something tangible start-up leaders can point to and dissect intelligibly as part of their business model/plan. "User Experience Design" is a vague erratic phrase from the dot com era that C-Level folks don't grok.
Familiarize yourself with the fundamentals of visual design (type, color, grids, layouts) by studying Mullet/Sano's Designing Visual Interfaces. Practice critiquing sites and products against visual qualities of communication of affordances and tone/voice/quality. Start the path of gaining that sensitivity, which takes years.
Start sketching and keep a sketchbook with you at all times. Jot down ideas, sketch solutions, and constantly iterate, fast. Jot down the reasons for/against possible solutions. Revisit, repeatedly, after reflection.
Know the basics of user research methods and cog psych principles, concepts like affordances, cognitive load/chunking information, basic user/screen/input ergonomics, Fitts Law, etc. A/B testing vs heuristic eval vs contextual inquiry, etc.
Start thinking about flow, scenario, tasks, goals, activities. Look at how you use your iPhone or Tivo or XBox or Microwave even. What's the sequence of actions, feedback/information loops, hierarchies of needs/values in getting tasks done, etc. Sketch out the flow of actions, accounting for error states or diversion paths, sub-paths, etc.
Read Don Norman's Design of Everyday Things. Great rundown of the basics of basic usability concepts and examples.
Always ask yourself how to simplify, simplify, simplify: visuals, behaviors, navigational paths/error states, and terminology.
Learn how to prototype, from click-throughs to HTML/CSS/JQuery or Flash/Flex/AIR tools. Study the digital behavior and affordances of online and desktop apps, and on your iPhone/Android device. Look at the timing, transitions, visual effects, all those cues.
Keep asking yourself how to make something better, in terms of visuals, behaviors, information architecture/navigation paths, simplifying and unifying elements. Start developing that sensitivity now so that in 3 years you'll be sufficiently valuable to a start-up.
And start designing something now :-) Either fix up an existing product or invent something as a hobby, for practice. Enjoy!
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