When you sign into the portal, click on the mSign product button on the left. It is the orange icon.
From here, select Templates on the left hand menu, and then click on the Create button in the top right.
From here you can choose to upload your template from your device or from the cloud.
Once you attach the file you would like to use as a template you will select the Next button.
You did it! You can freely edit the template from here with the fields you would like to be added.