How to add risers to existing stairs

Do your stairs have open risers (the part under each tread)? My basement stairs did, and that made the stairs inconvenient (when you drop things, they fall under the stairs) and dangerous (my smallest child could fit right through the staircase!).

In this video, I demonstrate cutting a 1x8" board to size, pre-drilling three pocket holes and three regular holes, then screwing it into the treads. This should work for any staircase with wood treads and a little bit of a 'nose' or overhang on each tread.

Mentioned in the video - Kreg Jig K4 Pocket Hole System: https://amzn.to/2VPz7n8 (though you can fasten the boards another way if you don't want to use pocket holes!).