1 - Loot the stuff in and around the plane. Hit suitcases with your axe. Eat meals in the plane until full. Open all the suitcases you see.

2 - Get to running! Avoid any villages (teepee / hut looking things). Find yourself a large body of water - be it the ocean or river. Avoid any areas with boats or structures of any kind.

I prefer running until I find the River - and there's only one really large River in the entire map! I follow the River east (look up at the sky and orient yourself by the sun), and when the River ends, I continue straight. There'll be an island straight ahead. Cannibals very very rarely frequent the surrounding cliffs. When looking west, the cliff on the right has a pond. The cliff on the left has plenty of rabbits, lizards, trees, and sticks.

3 - Plan to build your base with your back to a body of water, a cliff, or on an island. A hunting shelter will take 7 logs, and assorted sticks and rocks. This will take two trees.

If you want to build on an island, you'll build a raft on the water. This requires 32 cloth OR 4 rope (same thing) and two cut trees. For the time being, build a hunting shelter on the land nearest your island until you gear up to build your raft.

4 - Kill rabbits, lizards, and birds. I prefer throwing small stones until I build a bow (cloth, stick, rope). Once you get a bow, killing gets easier. You can also build small animal traps. Put those under tree areas.

Lizard skins will make you armor. Rabbit skins will make you bags for carrying extra sticks and rocks. Feathers will make arrows.

5 - Avoid cannibals at first. Try to not let them see you. If one sees you, try to kill it with your axe or bow. If 5 see you, I suggest running until armored and weaponed up.

6 - For your first caves, hit up the entrance of 1 closest to the river. Alternatively, hit up the entrance of 2 closest to the big pond.

7 - For relatively safe raiding, walk down the river on the Eastern most side of the island, where the two cannibal structures are. That side of the river almost never has cannibal raiding packs, and will at most have 1 or 2 starving cannibals. Break the statutes made of people parts (effigies) and take the stuff from the two structures.

8 - When you get braver, hit up the big cannibal village at the southern part of the island. Visit the Yacht and Cockpit regularly for supplies, as well as where you crashed. Visit caves 1 and 2 regularly for supplies too, as all of these locations respawn after a game day or two.