First lets add all the Host(A) records.
Right click the domain in the left windows
Select new host record
You’ll see this:
Now enter the IP in the box that says IP addres. Don’t add anything to name. This will make so the main domain, in this case justbs.us, resolves to the IP.
Once you have the IP set click the Add host button. A popup will let you know the record was added sucessfully. The IP you put in will remain except for the last 2 octets. You can now add a record for www.yourdomain.tld.
To do that type www in the Name box. You’ll see the www. appear in Fully qualified domain box. Now add the last 2 digits to the IP. These will be the same as the first record you added. Unless you want www.yourdomain.tld to forward to another IP. Continue this procedure to add, mail, ftp or any other subdomain you want to add. make sure you also add a wildcard record. To do this add an * to the Fully qualified domain box and set IP. This will allow any request to non-existent subdomains to forward to the root domain.
Now let’s add an MX record(Mail Exchanger).