How to add an SRV record for a domain?

To add SRV type of record, click on Add New Record, then select the desired domain from the ‘Hostname’ drop-down menu. Choose “SRV” for type, then fill in the value, service & protocol, weight, port and priority.

Example of SRV Record with syntax: IN SRV 0 5 80

You can read more information for the SRV record at Wikipedia