The guys have provided some good suggestions. In your earlier post you wrote that you have a compass. Use it. You can check your gps compass page and your track to get your general direction. But at .5 miles per hour a gps with no electronic compass will not fulfill your needs.
It has been suggested you use the track back mode. It is not a bad suggestion. This last fall I had my Garmin Legend in the Track Mode while hunting. After returning from a hunt on a steep slope I downloaded the track to my pc using Garmin's MapSource Topo software. It created a good map of my hunt. Because of the vegetation, and steep slopes I am sure I never exceed .5 per hour. I would have been off a cliff if I had.
I do not have my nose in the compass or the gps when hunting. I might take a bearing with the compass on location when hunting, or mark a waypoint(tracks, sighting, or water). Or I might hit the find waypoint option when it is time to head back to the pickup waypoint.
Gps units are not the answer to all needs. A gps with an electronic compass cost more and may not be worth the price. It depends on batteries and reduces the units operating time. A handheld compass is a better investment. I believe the new Etrex Vista C w/electronic compass, and extended battery life may be ideal for you. Garmin has as least five units with electronic compasses. Magellan has a number of models with electronic compasses. I recently saw Magellan Sport Trek Pro Color with electronic compass for $200 at one of the big box stores. A very good deal indeed.