Help with simple animations for a home page image

Greetings all, 

I am building a small website through Squarespace to replace my old one. My home page is an image I drew, then traced into Adobe Illustrator, now I need to add color, I'll probably use Photoshop. When finished I will have some very simple parts of my illustration animated, like a shadow figure of a person moving, or a star moving across a screen for an example. 

What's the best way to tackle this, as far as software? I imagine saving it as a gif then? I've done this but its been years and looking for the best and simplest route. 

Thanks for your help in advance, 

Phillip