I want to help and add detail locally

I do mapping with both my smart phone and with my Garmin eTrex 10. For hiking trails the Garmin does a much better job (better GPS acquisition, can set recording time/distance better, can to a time averaged acquisition for more accurate waypoints, etc.).

To use your GPS, figure out a way to export the tracks and waypoints into GPX format. On my current eTrex I simply plug in to the USB on my laptop and copy the files. On my old eTrex there was a serial to USB adaptor needed along with some special drivers and software on my computer. Your GPS should have some instructions on how to do it with your computer.

You can directly import the GPX files into JOSM (I am not as familiar with the iD or Potlatch editors). It is easy then to add or move trails as needed to align them with your track and to add things that you have set way points on (I do bridges, benches, picnic tables, trail junctions). For others, you can upload the traces GPX to OpenStreetMap (waypoints cannot be uploaded).

When you select an area for editing you can have your editor show all the traces for the area. So if others have uploaded traces you can visually average them to get a better trail location.

If the area you hike in is frequented by fitness freaks, there is a good chance that Strava has a huge number of tracks from either bicyclists or trail runners. You can use their modified version of iD at http://strava.github.io/iD/#background=MAPNIK&map=14.00/-122.3154/37.3989 to locate trails (they have a cool feature where they can locate the trail to the most common GPS location). Or in JOSM you can setup to use Strava heat map layers to manually add and align trails. Doing it this way you don't even need a GPS and you can get a pretty good location for trails that are hidden below the tree cover.

I don't use a GPS unit myself, I prefer to use my smartphone, so sadly I cant give you any tips on how to use your device, but I posted up a list of tips in another thread which might be of use in terms of adding/collecting information

You can find it here

Hi, a bit strange maybe, but who owns or maintains the tracks ? If there’s an owner of the area, woods or whatever and if so he could be the "owner" of the track, even if it’s governmental. It’s nice to ask them if they agree with your plans, you even might get some cooperation. It could be a European idea nevertheless.