Subaru 2008 IMPREZA - Manual (Page 278)

9-12
In case of emergency
(1) Connect one jumper cable to the
positive (+) terminal on the discharged
battery.
(2) Connect the other end of the
jumper cable to the positive (+) term-
inal of the booster battery.
(3) Connect one end of the other
cable to the negative (
−) terminal of
the booster battery.
(4) Connect the other end of the cable
to the strut mounting nut of the vehicle
with the discharged battery.
Make sure that the cables are not near
any moving parts and that the cable
clamps are not in contact with any other
metal.
5. Start the engine of the vehicle with the
booster battery and run it at moderate
speed. Then start the engine of the vehicle
that has the discharged battery.
6. When finished, carefully disconnect
the cables in exactly the reverse order.