1. The quickest and easiest way would be to create the image from the ArcGIS Online map viewer:
2. A slightly more advanced way would be to build a Web Mapping Application (using the ArcGIS Web AppBuilder) and add a print widget to this app.
Hope this helps :)
Were it me, I'd just do a screen capture using any one of a number of options (I use Snagit a lot) and then just copy and paste into your Word document.
The things that will make a big difference are the size. If it's downsized in Word, you'll likely notice a degradation of image quality. So capture at a size that is closest to actual when added to your Word doc.
Better yet, use one of the map-centric configurable apps to create a live interactive alternative, and add a link to that in your Word doc, along with whatever graphic you want to include. Best of all worlds...