Design custom bar coaster for advertising business

I need assistance designing and formatting a custom bar coaster (4 inch, round) for advertising our business. Coaster is double sided, and we need advertising on one side using our visual and verbal brand guidelines (we will supply for you) with a QR code linking to our website on the other. We will be ordering from Templi.com and need the final design to be formatted so we can upload the design for purchase (see attached file for specific requirements for formatting). We need someone willing to work collaboratively and provide edits as needed. Thank you!