What coordinate system for compass direction

[KevinEvringham]

I'm a total newbie.  I've tried to google this but have not found a solid answer.  Essentially I am making a land navigation (orienteering) course and am using a trimble juno 3b with arcpad and arcmap 10.  I am not making paper maps, ever.  All I want to do is stand at a tree, make a point walk to another tree, make a point then tell other people to go X direction and X degrees.

I can do all of this already on the GPS device and in ArcMap yet looking at the numbers I believe the degree's are off a little leading me to believe perhaps I am using the wrong coordinate system.  Currently both the GPS and arcmap are using:
GCS_WGS_1984
Datum: D_WGS_1984


Is this the correct coordinate system to use as a reference for a compass? 

Any help is greatly appreciated.

[KevinEvringham]

Coordinate system may not even be the correct question.  It may be related to the COGO Grid to Ground function.  Anybody know about either of these?  Please do not direct me to the help manual as I have read that without satisfactory results.

[BrettBlack1]

I think I understand what you are saying. Is your Juno unit using SBAS (WAAS) for differential corrections? If so, then your GPS Datum in ArcPad should be set to ITRF and your ArcGIS Desktop projection should be set up so that it properly translates from ITRF to what type of projection you are wanting to use.

If you do not do so, your field collected could be off +/- 1m depending on where you are located in the world.