Feed him cake and pay him lots of money. OK, so you're back from reading the funny stuff. There are reasonable things you should do to keep your farrier happy. Clients are happy because they have a farrier they can rely on. A worry free relationship with your farrier can be priceless.
Farriers benefit because good clients are just as reliable as good farriers.
Follow your farrier's recommendations about this. Provide a safe, clean quiet place to work. It should be easily accessible to your farrier's rig in all weather. It should have easy access to water and electricity and it should have good ventilation. Make sure your horse is safe to work on.