Are you referring to the Windows Snipping Tool or is there another application called Snippet?
If it is the Windows Snipping Tool then the snip itself is captured as a graphics picture in one of several selectable formats. But being a picture if you try and print it from Windows then you can select the size of the picture in only a few different ways, one of which is full page. If you import the snip into a photo programme you may have more flexibility or you can import it as a picture into Word and then drag it to a size that suits you.
If you are indeed talking about a programme called Snippet then ignore the above as I can't help you.