Learning the hotkeys... what should I learn now?

So I learned all the most common hotkeys for eco (build villagers, farms, houses, etc) now I lack hotkeys for the military.

What should I learn first? Should I learn the hotkeys to build the military buildings, or is better to learn the hotkeys to select these building first?

I think is not a silly question because learning to build fast may help to be ready faster, but actually learning to select these building fast may help to have a steady production queue over the time.

Yeah, I like to focus only on one thing before making the next step, so what is more in important in your opinion?