Go to Piskel and create your own spirt (or moving character in a game). Make sure you make it animated by copying and moving parts of your original. It should be about 5 slides. Once finish go to the export tab and download as GIF. Click here for a screenshot.
Then Go Here!
Go to Scratch and click on the "See Inside" button. This will bring you to the editable code page. We aren't going to change anything in the code and instead replace the spirts and backgrounds to make it our own! Here you can upload your newly created sprit! Here's a quick video "how-to" on replacing spirts.
Finding yourself with some extra time? Go ahead and use Google Drawings to create a different backgrounds, titles and other elements. Make sure to download them as PNG files.