to start press z then space to start and make it work 1 2 3 4 5 6 7 8 9 0 to change color hold down mouse or c to draw z to control with mouse (most preferred) x to control with arrow keys (for right angles or diagonals) space to clear e for eraser r to make pen-size bigger by five f to make pen-size smaller by five g to reset pen-size you are going to have to reset pen-size after using eraser
if you want to, leave suggestions in the comments hope you like it feel free to remix diagonal arrow drawing doesn't work properly as of now https://scratch.mit.edu/projects/647875/#editor