You can move left and right a bit as Lara slides, but this isn't really necessary until the camera shifts to show the slope below and ahead of you.

Then you need to steer left...

...then right to avoid the fence-like barriers made of planks and barbed wire. These can do a lot of damage if Lara crashes into them.

A bit farther down the slope, there's a burning pile of wreckage. Avoid it by steering around it to the right or going up the ramp to the left.

If you hit the wreckage...

...Lara will be impaled (horribly) and you'll have to start the sequence again.

Steering up the wooden ramp on the left (as shown above) seems preferable.

You'll come out on the other side and slide down onto a wooden ledge.

If you go to the right, you'll need to avoid several more spiky barriers...

...shown here...

...before reaching that same flat, wooden ledge. As Lara rolls out onto this ledge, the camera shifts again to point uphill.

She tumbles over the edge and you must press Interact to regain her grip or she'll plummet into the chasm below. Pull up onto the wooden ledge and wait briefly for more debris to come tumbling toward you.

As soon as the camera points to the right, run forward and jump across the gap onto the next wooden ledge. You receive 100 XP for surviving and find yourself in a brand new area.