1. Include a meta description on the page.

2. The image file size should be the smallest possible
There is no way to shrink the image file size in Cascade. Image file size can be shrunk using software outside of Cascade.
3. Include key terms in the page name and keep it short

When adding the page name do not use terms like: and, or, but, it. The page name will be the URL of the page therefore keep it short.
4. Use headings and correct heading order.
The title of the page is heading 1 and that should only be the only one on a page.
Following numerical order, the headings should be included.
Inserting a heading is done by highlighting the heading then going into Format --> Formats --> Headings

Other Resource
Images larger than 1 MB issue in Siteimprove
Headings are not structured correctly issue in Siteimprove