Notch a V in the edge of the softwood base (the fireboard) and rest the softwood on the ground.
At the V’s point, create a depression that is the diameter of the hardwood (the spindle).
Place tinder below the V notch (so that the ember will fall onto it).
Place the end of the spindle upright in the depression.
Hold the spindle between your palms and rub them together, back and forth at a constant rate, while moving your palms slowly up and down the spindle to simultaneously rotate the spindle and apply downward pressure to maintain firm contact with the fireboard. The spindle end at the fireboard will become hot from friction and eventually ignite.
Allow an ember to fall onto the tinder and blow on it gently.