To put you pencil down click d to bring it up press u. When it asks you to pick a color press the key you see it means when you click the key r your pen will be red and same with the other colors. And if it wont let you draw click d. Also special thanks to SGChase18.
it took me like 3 days, but i finished if i have typos tell me and i there is something wrong tell me and i will fix it. Also use the arrows to move the pencil