Craft a trap

You look around you for any material you could use to make a trap. There are fist sized rocks, a few broken pieces of glass, a few arm length broken tree limbs and some damp kelp.

After a few minutes you decide to craft a spike trap at the opening of the tree shelter. Taking your knife in hand, you sharpen all the tree branches to a sharp point and jam each one about 4 inches apart and at a 45 degree angle, making a bristling fence of wooden spears that could easily impale some unaware beast.

You also figure that while anything struggled to make it through your first line of defense, you had a fair amount of powerful ammunition in the form of those fist sized stones. You neatly pile up the best sized ones close to your sleeping spot.

The glass comes in handy as a kind of caltrops that you strategically drop in a concentrated area between the spike trap and your resting spot.

All done!

Now it's time to sleep...