If anyone really wants to make your Spirit boards more official-feeling, you can paste your printouts onto actual chipboard, which you can get pretty easily from Amazon (for example)!

I used this chipboard (ordered from that exact amazon listing). It's 2mm thick. I printed the labels out on a laser printer, used 3m super 77 spray adhesive to glue the paper onto the chipboard, then used a rotary cutter, metal ruler, and self-healing cutting mat to cut the dividers to size.

I had all of this stuff around the house - I've PnP'd several games, so none of this stuff is new to me.