Get THIS relay or equivalent. Terminals are marked "battery" "horn" "switch".

1. Mount relay in a good spot on inner fender or firewall. Be sure it's mounting feet touch bare metal.
2. Wire from always hot fuse to "battery" terminal.
3. Wire from "horn" terminal to horns. Jump from one to the other or splice.
4. Wire from column to "switch" terminal.

Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn