Made a change to the rules so they are a little more clear. By all means you can draw on a electronic device with a tablet or mouse and upload that, and it is a little more preferred since it makes it easier to see the detail and work someone might otherwise miss if it's a photo of a paper. But drawing on an electronic device won't boost your score any higher, just be aware if you do take a photo of a picture you drew in real life, that the photo is nice and clear so we can see as much detail as possible.
Also, if you wish to change your picture you can edit your entry up to the last minute and make changes, however try to edit your original submission post instead of making a new post. This is so we don't mistake your final entry as a second entry and disqualify you.