How to move a site to a dedicated pool?

Control Panel V5 > Hosting Control Panel > Advance
You will need to create the dedicated application pool first, click here for the details
 
1. Log into your hosting Control Panel.
 
2. Go to WEBSITES > Manage Website
 
3. Click "..." beside the target site, then click "Application Pool", you will be able to select new dedicated pool you just created for your site.