No, it is not necessary to involve your webmaster if you use a basic template. MTN has made it easy for you to create a template to show your needs on your web site. With a simple basic template (a plain grey one is initially created for you) you can update the colors, menu items and logo to look approximately like your web site.
However, if you want an advanced template, or exact replica of your web site, you can follow the written and video instructions on the Help button on the Create/Edit My Template (under Settings). The process involves simply copying your HTML coding from your header and footer of your website. However, you will likely need assistance from your webmaster to ensure every page of your sign up process looks good and works well across all browsers.
You can access both the Basic and Advanced options by going to Settings on your Dashboard and clicking the Create/Edit My Template button underneath the Customize MTN for Your Website header.