How do I copy a modified Pinboard theme from one site so I can paste it onto one of my other sites and retain the modification?

I just discovered this marvelous theme and want to use it on several of my sites. I’m in the process of modifying my first site with different, standard options like background, layout, colors, fonts, etc.

All of this takes a lot of time so my goal is to end up with a master site with Pinboard modified the way I want it…then use Filezilla to copy the Pinboard theme from the WP-content subdirectory of the master site and then paste it into the WP-content subdirectory of another, already existing WordPress site with all of the modifications I made to the master already done to the slave site.

The problem is that I’m only getting the default theme when I do this.

I’ve got to believe that there is an easy way to accomplish what I want to do but I am apparently clueless as to the steps required.

What am I missing?

TIA,

Robert