This may sound dumb, but the best way is to work directly with (good) designers on projects. Like engineering, design is something you learn through experience

This may sound dumb, but the best way is to work directly with (good) designers on projects. Like engineering, design is something you learn through experience. You can be taught the basic patterns and rules of thumb easily enough. You will however, end up running into situations where things don't fit nicely into those patterns pretty quickly.