Chapter One - Limbo
You will reach a selection of wooden beams and a rope on the precipice of a cliff. Look for the crate beneath the contraption, and pull it to the left (using X/B). It is tethered to the platform, so pull it all the way before climbing over it. Press jump and your character will automatically grab onto ledges. Press it again to pull him up.
At the top, jump onto the rope and slide down to the beam. Drop down from this to reach the lower level.
Descend the rope to continue
Head to the right and jump in the boat. It will take you across the water. Once on the other side, jump out and use the action button (X/B) to grab the boat and pull it to the right. You can then use it to give you a platform to jump up to the next section. Use the ladder slightly hidden to the right to climb up and then jump left to reach the rope.
Proceed to the right through the darkness. Head through the first rays of sunlight, but stop when you reach the second, as there are some traps ahead.
Look out for the bear traps on the ground.
You can't jump both the traps, so pull the left-hand one away, creating a sufficient gap in between the two to allow you to clear both in two jumps.
Continue until you see a rope with an animal carcass hanging from it. Drop into the pit underneath, and pull the trap to the right underneath the rope. Climb back up to the left, and jump on the rope. The carcass will trigger the trap, allowing the rope to reach higher – you can then get to the ledge up to the right.
Follow the path until you come to another large log. Jump onto it, and then immediately back to the left. This triggers a boulder to come hurtling towards you, but it will miss you if you are far enough left. Jump over the boulder and continue right.