Take a look at the installation manual from Carefree:
https://www.e-carefree.com/ecarefree30/product-library Scroll down to "Slideout Awnings" it's the middle selection, "Slideout Cover".
On the cover of that manual you'll see pretty much how it's positioned, and the manual will describe exactly what you need to do.
If you feel "up to the challenge" after reading the book and if you have someone to help you position the slide cover so you can thread it into the awning rail you'll have to install, the rest is pretty much just "wrenching it tight".