How does one get better at design?

that depends on the methods you used. it's one thing to go 'ooo, i like that header graphic i need to learn how to do those effects" and to go "oo pretty, i want one of my own". you just become dependent on taking other people's ideas.

the only thing that makes you better creatively is experience/practical practice. you can know how to do every effect photoshop is capable of, but if you can't conceptualize ideas to apply them, you're not much better then the other guy who can't apply effects to anything.