To start our game, we will need a character to fling through the air. Angry Birds, of course, used birds as its main characters, but we can use whatever we like.

At the top of the sprite list, you should see the three buttons shown in the previous screenshot. The first lets you draw your own character, the second lets you use an existing image (including a wide range of images included with Scratch), and the third gives you a random image from Scratch's selection.

If you click on the first button, you will be shown the following window; it has plenty of easy-to-use options for creating your own drawings. Hover your mouse cursor over any of the buttons to see what they do.

The second button brings up a fairly standard file explorer with lots of neatly categorized images. This is the option I will use, but feel free to do something different.

Once you have drawn or selected a sprite, click on OK to add it to the game. If you choose not to use the default cat character, right...