If you're building into a wood case or for a wood surface, you can use these:
binifiMux 100 Pieces M3x6mm Carbon Steel T-Nuts Zinc Plated 4 Pronged Tee Nut
Litorange 240 Pieces M3 Male Female Hex Brass Spacer Standoff Screw Nut Threaded Pillar PCB Motherboard Assortment Kit
You'll need the following:
Here's the process: