To set up your domain to work with Google Sites, please follow these steps:

1. Sign in to your Dynadot account.
2. Select the "Domains" tab in the main menu.
3. Check the box next to the domain name(s) and click on the "Set Name Servers" button.
4. Click on the "DNS" tab.
5. In the "Domain Record (required)" field, select "Forward" from the drop-down menu and then enter https://sites.google.com in the "IP Address or Target Host" box.
6. Below that record, create a new one. Select "TXT from the drop-down menu and then enter your Google verification string in the "IP Address or Target Host" box.
7. In the "Subdomain Records (optional) section, enter "www" as the subdomain, select "Forward" from the drop-down menu, and then enter https://sites.google.com in the "IP Address or Target Host" box.
8. For your second subdomain record, enter "calendar" as the subdomain and "CNAME" from the drop-down menu, then enter ghs.google.com as the "IP Address or Target Host" box.
9. For your third subdomain, enter "docs" as the subdomain and "CNAME" from the drop-down menu, then ghs.google.com in the "IP Address or Target Host" box.
10. Lastly, enter "mail" as the subdomain and select "CNAME" from the drop-down, then ghs.google.com in the "IP Address or Target Host" box.
11. To enter your MX records, scroll down to the bottom and find the "MX Records" section. Enter in aspmx.l.google.com, alt1.aspmx.l.google.com, and alt2.aspmx.l.google.com.
12. Click on the "Save DNS" button to save your changes.

Your settings should look similar to what is shown below: (click on it to see it larger)

Google Sites CNAME Example