Press Space to start a new climb. Move with the arrows or A/D. Space jumps, and twice more in the air to flip. Jump off walls to climb them.
F strikes with the spear. Over birds, lanterns and thorns it bounces you up. C throws it into wood to stand on, and C again calls it back.
Light shrines to save your place. R takes you back to the last shrine, Esc pauses and M mutes. A gamepad works too.
Signed in, a new climb in one sitting is ranked: 1,000 per shrine lit. Reaching the top adds 10,000 plus a speed bonus that shrinks with your time and falls.