Step 1

The Studio is designed for A5-A4-A3 sizes. The first two are defined by Figma, the latter isn't. But we can create it from an A4.

Step 2

Add an A4 frame to your workspace.

Step 3

Go to the properties pane and double the Width by multiplying by 2. You do this to add "*2" to the box.

Step 4

Step 5