No scanner
do you have a camera/phone with a camera, you can just take a picture of it
it wont be quite as high quality as with a scanner but it works
also i draw on paper, take a picture of it with my phone, and then trace over it in firealpaca (which is free and works on mac + windows), and even though i use a mouse (and am starting to use a laptop trackpad) i can get pretty smooth lines by using the correction feature
so if you do want to draw digitally with a mouse firealpaca is a good option