The Graham Ski Trail is an established trail but is not on any maps that I can find. Here is a map that has it as accurate as I could 
make it and should help you find it. It is easier to find from the Gulf of Slides Ski Trail but from the Sherburne Trail it may take a little looking to locate it as its entrance is a little camouflaged. Here is a link to a GeoPDF
http://www.chauvinguides.com/wp-content/uploads/2017/01/graham.pdf
Below is the QR Code you can use to import the GeoPDF into Avenza Map App on your phone.
I am also including the Graham Trail GPX (Some browsers add a .xml extension, delete the .xml leaving only the .gpx extension before saving) and .KML file of the trail.
