You can’t change the template size but you can make Chun bigger. Click on her layer and hit control+T. This will allow you to resize her. Make her whatever size you need. Once you are done, double click on the zoom/magnifying tool. This will zoom at the exact print size quality and will allow you to check Chun’s print quality and figuere out if you’ve stretched her too much. If she looks blurry The you need to make her smaller or find larger image.
Protip number 1: if she’s too blurry re insert the image and resize as opposssed to just making smaller again. Image stretching degrades the image quality.
Protip number 2: always uses the double click on zoom tool to check print quality. And move around without zooming out by holding SPACE bar .
Source: I have a bachelor’s degree in GD and do this for a living hehehe