Adding a CHM help file to my Shiny site

I have a Shiny site used by inexperienced clients to view pump performance data. I wrote a comprehensive guide in Word to help them use the web pages presented by Shiny. However recently i was asked why I could not just add a link to the Shiny page to open a windows help file (CHM file). I have created the CHM file, but how do I add this to Shiny and make it accessible, either by clicking a link of pressing F1 while browsing the site?

thanks

Simon