New to GPS

[TwoTone]

I've been trying to research this and haven't found an answer yet.

I've download My Trails (really nice) but there are a few local trails missing.
I've also managed and understand how to get the Topo and My trails on my 810 and that is working well.

I've found GPX files for the missing local trails but how do I combine My Trails with several GPS trails to overlay them on the topo?

Also, if you have recommended tutorials that would be great.
Thanks

[Seldom]

Send your GPX files to jbensman, MyTrails author.  He'll incorporate them in his next build.  This site discourages modifying the work of other mapmakers.

[TwoTone]

I'm not looking to modify his file.  I'm just looking for a way to show both on the GPS at the same time.

[Indrid Cold]

If the 810 has a track manager, send the .gpx tracks to the GPS and them enable them as "show on map" in the track manager. Also, send the .gpx files to Jim as he updates the My Trails mapset almost weekly and you will not need to enable them any longer.