Buick 1994 Roadmaster Owner's Manual page 197

10. Now start the vehicle with the good battery and run
the engine for a while.
11. Try to start the vehicle with the dead battery.
If it won't start after a few tries, it probably needs
service.
12. Remove the cables in reverse order to prevent
electrical shorting. Take care that they don't touch
each other or any other metal.
U
GOOD BATTERY
DEAD BATTERY
Remove cables in this order.