If you would like to print a map you'll first need to download it. To do this, on your map, click on the download button in the lower right corner of the Map Layers window. 

Clicking this button will bring up a new window. 

Currently, the only option output is a PNG file but soon there will be options to share the map through social media, link directly to it, or convert to a PDF file. For the time, click Download to download your map. Next, open the file on your computer and select the print function.