Create fonts directory inside .local/share:
mkdir -p ~/.local/share/fonts
cd ~/.local/share/fonts
Download the font (e.g. Fira Code):
git clone https://github.com/tonsky/FiraCode
Update fonts cache:
fc-cache
You can list available fonts with:
fc-list
For dwm, edit config.def.h:
static const char *fonts[] = { "Fira Code Medium:size=14" };
static const char dmenufont[] = "Fira Code Medium:size=14" };
Change the font name and size for your needs.
Remove config.h and re-compile:
doas rm config.h
doas make clean install
Restart dwm to apply changes with Shift + Mod + Q