If your website does not use a CMS, follow the guide:
1. Create a subdomain on your hosting. For example, static.example.com and move static content to it. You can do it in your hosting provider administration panel in the subdomains section;
2. Create a CDN Resource in your control panel. Fill the Origin Source field with static.exampe.com. In the CNAME field, enter any domain name you want to use for content delivery. Learn more on CDN Resource setings in the article.
3. Add you CNAME record to your DNS.
4. Integrate the website with a CDN.