As PALU says, there aren't really any avenues for trading for profit. Somewhere, you have to be creating primary goods. In that regard I can think of three options:
1. Food: You hunt/trap loads of animals, turning most hides into cords, and produce quality food for the people.
Skills: Cooking, and a cluster in either hunting or trapping
2. Hides: You trap for the quality fur-bearing animals and turn out hides in exchange for food and tools.
Skills: Hideworking, trapping, something to escape Njerps -- speed/stealthiness, timbercraft also useful if you're not strong
3. Woodworking: You create traps, boards, bowls, etc.
Skills: Timbercraft, carpentry... probably want good dexterity, endurance, will in the base skills
I think 1 is out for you, because you want to trade for food to survive.
3, as PALU mentions, can be repetitive. Also, if your character isn't big and strong it can be difficult to do well.
2 seems like the best option for me. If you just never trade for a shovel then trap fences are out (and the only consistent trapping method where you get lots of food), plus being small when digging holes is annoying anyway. Having a good supply of furs means moving around a bit and having traplines in various regions. Plus, the "trapper/fur trader" character is very satisfying from a role-playing perspective. In a recent game I had a "fort" by the Driik and another by the Seal Tribe, and would make seasonal trips trading fur for tools in the south and tools for fur in the north. Doesn't make you rich, but feels very satisfying.
Edit: Added skill listings to more answer direct question.