When Perpich said “ you are your best asset” he meant that the first thing you need to do is keep yourself safe. Think of the consequences and use your brain to control your actions. There are lots of things in Brian’s pocket ,maybe he could use his  hatchet.

Brain is his best asset because he can think and he can control himself.

Now Brian has to find water and food until the Canadian Army comes and rescues him, but it might take the searchers a long time to find him because he was going the wrong way for more than three hours. It wasn’t according to the flight plan, but Mr. Perpich always said to be positive.