Sorry but it will not be very clear what to do even with a video. Try to follow the instructions. With up and down keys you select one of four binary registers. With left and right you increase or decrease the binary number of those registers. You will see not 1 and 0 but black blocks representing 1's. I don't even remember how to play it :P
Now I remember. The 1's of the last binary number of the four registers, represent gates, those gates will stop the flow of water that comes from the left of the binary tree. The binary tree is that weird simetric thing you see onscreen.
The other binary registers are conditional interruptors, (the first two)
The third binary register is the "negative" of the fourth.
The first binary register is the negative of the second one.
By negative it means 1 are converted to 0.
I hope it's clear. I know it's not. :)