Whether you design or do layout, welcome from PA.....................................................
It's kinda like the chicken and the egg deal. They overlap so much it ain't funny. Most of what you're gonna strive to look out for will be picked up by listening to your coworkers. Some things will be about composition, to color, to process of fabrication to overall cost for a finished sign. Some people are good with electrical backlit signs, some with billboards, some with airport trim signs to just some company's logo and copy in front of their building. Take it all in, listen and ask the questions your coworkers can't directly answer..... here at s101. We'll either know or give a lotta B/S that'll sound good.