Spoofing can be prevented by using a variety of authentication methods.(Eg: SPF record,DKIM record..)
Steps for adding SPF record
~~~~~~~~~~~~~~~~~~~~~~~~~
1. Log into control panel.(https://control.bytehouse.co.uk/cp/)
2. Select the desired domain from "All My Domains" tab.
3. Select "New Record" from "DNS Zone" tab.
4. Select the "type" as "TXT" from the drop down menu.
5. Generate the Value using SPF value generator websites and update to value field.
(Eg:http://www.spfwizard.net,www.royhochstenbach.com/projects/spfgenerator)
6. Click on "Save" button.(Note: There will be a propagation delay of 10 minutes)
7. Check "TXT" entry using "dig TXT" command.(Eg:dig TXT domain name)