You'll have different tools to help bring your drawings to life. The better your drawing, the easier it will be for your friend to guess, and the better the chests you'll get throughout the game.
If you don't like what you've drawn, you'll be able to discard your drawing by tapping on the trash bin. This means you'll have to start all over again. You'll also be able to undo your strokes by tapping on the backwards arrow underneath the canvas.
You'll be able to use different strokes and tools while you make your drawing. In order to do this, you'll have to tap on the one you want to use. If you wish to change it, you'll have to tap on a different one. You'll get more colors and strokes as you level up your tools.
Keep in mind that drawing letters or numbers to help your opponent is not allowed.