Tootfinder

#GPS is a cool thing. Even if the reception's poor and precision low, it's hard to get lost. Add a reasonably good digital map (#OpenStreetMap FTW!) and we can easily plan #hiking trips to optimally use the time available to us. We can check whether we're following the planned route, our pace, and change the plan if necessary.
But what if GPS doesn't want to work, and our trip goes through a uniform #forest with no specific orientation points, and doesn't follow a marked trail (or we don't know about it, because the map ain't that good, after all)?
Then you need four things: our good digital map, an initial reference point, a clock and a roughly stable walking velocity. A magnetometer or compass is also useful. It's not as convenient as using automated navigation, but it's totally doable, and you don't have to give anything up.
You've got the route initially planned, and estimated time of arrival. You determine the correct direction, measure the distance to the next turn, and compute how long it'll take to get there. We move the starting point on the map to that turn, and when we get there, we verify that ETA matches. Turn and repeat.
There's a bit of a conflict here. On one hand, we want to walk at a constant pace, to keep ETA stable. On the other, we want to walk as fast as possible, to have some leeway in case it turned out map was wrong somewhere and we end up losing 10 minutes straying. However, if crossroads and orientation points are reasonably dense, we can easily adjust for minimal changes in ETA.
One more thing: if we get lost in a polish forest, #mBDL to the rescue! We walk until we find another pole with sector numbers. Of course, you're usually going to walk long until you find one, then have to figure out how to move the position from mBDL to your regular map, but it's doable. Reminder: you have to read numbers "from inside", i.e. if you're looking at the pole in front of your, and it states 76, then it means 76 is *behind* you, and the number ahead of you is painted on the other side of the pole.