NPrinting is actually quite complex enterprise tool and I would suggest training for everyone who did not have one. On top of that you should have strong QlikView or Qlik Sense developer skills to understand what you are doing with NPrinitng and how much impact you will put on server.
The easies and simples way will have quite poor quality. You will have not much control over image quality and object size. So if you are going to use individual images you will have issues with fonts, labels sizes on them being different and again you may have troubles with cropped labels or scrollbars visible (depending on what is on your dashboard)
Excel or pixel perfect template can be used to recreate your dashboard but which one would be best depends on what is on this dashboard (kinds of charts tables etc + layout)
If you go for Pixel Perfect and you have no experience you will learn that this is more advanced tool and requires knowledge...
Best starting point is https://help.qlik.com and its NPrinting section. Go through tutorials there to get the basic features covered.
My personal opinion is that each dashboard should be thought through. I would consider prons and cons of the template I would need to use to build it and most of all I would consider possibility of using native excel or pixel perfect chart or tables features. That way you would achieve much better quality and better control over what you build.
cheers Lech, When applicable please mark the correct/appropriate replies as "solution" (you can mark up to 3 "solutions". Please LIKE threads if the provided solution is helpful to the problem.