Adding merge fields to Contact Emails

I’m looking at using the send email to contact function to send individual emails. I have been trying to add merge fields to the email body. I can get it to work but cutting and pasting from a draft campaign email but I can’t see a way to add them from the email creation tool. Does anyone know how to do that more easily?

These are designed as ‘one-off’ emails, and as such, wouldn’t have merge fields (thought process is that if there is info you need to include, you can copy/paste it).

If you are going to send this type of email to people individually on a regular basis, use the ’template’ feature and create a base template with this information (Using merge fields), and then use that template to start the one-off emails.