In Hatchet, how does Brian attempt to start a fire?

In Chapter 6, Brian laments not having matches as he looks out at the vast amount of dry driftwood around the lake. He tries his best to think of how experts start a fire and begins to rub two sticks together. After ten minutes of rubbing the sticks together, the sticks are still cool to the touch, and he fails at starting a fire.

In Chapter 8, a porcupine enters his shelter and Brian throws his hatchet in its direction. The hatchet bounces off of the rock wall and creates tiny sparks. The next day, Brian wakes up and realizes that his hatchet is the key to starting a fire. He examines the wall of his shelter and notices that the hatchet struck the darker rock. Brian then begins to strike the blade of his hatchet against the dark rock to create sparks.

In Chapter 9, Brian takes patches of birchbark peelings and shaves them to make birchbark fluff. He then takes the fluff and forms it into a nest with a depression in the middle. Brian uses his hatchet to create sparks which land in the nest, and he blows on the embers to create fire.

How does Brian attempt to start his first fire in Hatchet?

Gary Paulsen's novel Hatchet is a story of survival. Thirteen-year-old Brian Robeson, traveling to see his father,  is stranded in the Minnesota woods when the pilot of the plane dies from a heart attack. Brian is left with no way to communicate, and very little hope for rescue. He must learn to survive on his own, with just a small hatchet and the clothes he is wearing, along with a few token items in his pockets.

Brian tries to create fire by rubbing two sticks together in chapter six, but he is unsuccessful. In chapter eight, he realizes that his hatchet may be the answer to creating fire. 

"The hatchet was the answer. That's what his father and Terry had been trying to tell him. Somehow he could get fire from the hatchet. The sparks would make fire. Brian went back into the shelter and studied the wall. It was some form of chalky granite, or a sandstone, but imbedded in it were large pieces of a darker stone, a harder and darker stone. It only took him a moment to find where the hatchet had struck. The steel had nicked into the edge of one of the darker stone pieces."

Brian found flint in the rock and was able to use it to create sparks. He still struggles to start a fire, though, even with the sparks. He tears up the twenty dollar bill he has, which is useless to him now. Then he eyes a birch tree and is able to use the papery bark as a fire starter. He has to shred the bark into threads and make a sort of nest out of it, so the sparks will catch the bark and still have enough air to survive. It takes him several hours, but he successfully makes his first fire in chapter eight.