DS3Vita
Enable the plugin:
Add ds3vita.skprx to taiHEN's config (ux0:/tai/config.txt):
*KERNEL
ux0:tai/ds3vita.skprx
You need to refresh the config.txt by rebooting or through VitaShell.
Pairing the controller:
Download this tool (or this other one if you want to compile it yourself)...