[codeptualize]

Lots and lots of practice.

Your first designs are going to be horrible, no way around it, just keep going, compare, reflect, learn, and things will get better over time.

If you can get feedback from experienced designers that will help a lot.

As to resources; Others mentioned Don Norman's book (and nngroup.com), great suggestions. I would also spend time looking at good designs and trying to figure out what makes them good. Just ask "why" about everything. "Why is this button this color, why is it this size, why is it placed here? etc etc".

Good design is about achieving goals, the better you get at focussing on those goals, mainly by asking "why", the better your understanding of design and your own designs will become.