Open the page or pattern you wish to print within the app. Click the printer button in the top right of the screen. If your device is connected to a printer, you will be able to set the print options and send the pages to the printer. If you are not connected to a printer, you will be able to save the pages as a PDF. Then you can send it to another device for printing if needed.
Please note, you are only able to print up to two pages at once. If you wish to print more, you will have to start again, selecting those pages.