MarkerClustering Help

I’m trying to figure out a way to use Marker Clusters. I have a map with markers all over the country, and they are primarily focused in major cities. without zooming all the way in many of the cities look like they contain only one or two markers, when in fact there can be as many as a dozen plus in some cases.

I see this is a possible alternative, but not sure how to integrate this (not good with javescript)
https://stackoverflow.com/questions/11637130/google-maps-v3-marker-clustering-without-use-of-markerclusterer-plugin-or-fusion