It's always a good idea to lay out your
stairway risers before you nail them in place. I've seen carpenters grab
individual stair risers, from a pile on the building foundation and nail
them up one at a time.
You can save yourself a lot of time by spreading out your stair risers
(as shown in picture above) before nailing them on. Be careful nailing
your treads and risers on, because they can be dangerous to walk on,
until they are completely fastened.
Split Level Stair Framing