There is something you should look for to avoid going in the opposite direction:
The Sun. At noon, the sun is roughly in South (or in the north on the southern hemisphere),
so if you are heading north and have the sun in your face, it should ring a bell.
When do you need this technique?
If you are out there without a map, and you don't know where you are,
but you know that there is a road, trail, stream, river
or something long and big you can't miss if you go in the right direction.
And you know in what direction you must go to get there, at least approximately what direction.
Then all you need to do, is to turn the compass housing,
so that the direction you want to go in, is where the direction of travel-arrow meets the housing.
And follow the above steps.
But why isn't this sufficient? It is not very accurate.
You are going in the right direction, and you won't go around in circles,
but you're very lucky if you hit a small spot this way.
And that's why I'm not talking about declination here.
And because that is something connected with the use of maps.
But if you have a mental image of the map and know what it is, do think about it.
But I think you won't be able to be so accurate so the declination won't make a difference.
If you are taking a long hike in unfamiliar terrain,
you should always carry a good map that covers the terrain.
Especially if you are leaving the trail. It is in this interaction between the map and a compass,
that the compass becomes really valuable. And that is dealt with in the next lesson.