Just press the green flag. To paint press "down arrow-key". To stop painting press "up arrow-key". To change the brush size press: 1: to go to original size 2: to make it twice the size as 1 3: to make it twice the size as 2 4: to make it twice the size as 3 5: to make it twice the size as 4 And "space-bar" to erase.
Next update Better looking paintbrush.
