Subaru 2004 Legacy Owner's Manual page 47

Seat, seatbelt and SRS airbags
more slowly. If the belt still cannot be unlocked, let the
belt retract slightly after giving it a strong pull, then pull
it out slowly again.
4. Insert the tongue plate into the buckle until you
hear a click.
1-22
5. To make the lap part tight, pull up on the shoulder
belt.
HS1050BA
6. Place the lap belt as low as possible on your hips,
not on your waist.
HS1051BA