Arduino Mega Sheld

Hello,

I’d like to try Upverter for an arduino project. A custom made shield onto an Arduino Mega.

To make it easy for me I’d like to build from a ready shield component or layout.

Searching for this, I find a few candidates but the most promising is just a square where it just tells me to use a Template and a number.
Searching for this number brings up nothing.

How should I proceed?
Thanks
/Jonas