Hi, looking to understand the order in which i finish the stairs.

I am just about to finish my basement stairs. When they were built, the carpenters just left the stairs ends "open" with no stringers. I've built some walls along the stairs, finished with drywall, and am now looking to put on some hardwood plywood trim along the riser, and some maple stringers along the sides. My question is what should I put down first, the plywood for the riser, and then the stringers or stringers first, and then the risers sandwiched between the stringers.

thanks,
mike