The method in that thread is fine, if you are already minded to push the rule to one side, the one about not flying over built up areas.
It would be silly of me to say you won't catch me doing that, if only because 25 or so years ago I decided to live and 'play' in the country, so I'm not faced with the problem.
To go back to the original question, and let's go for the worst case scenario by assuming you are new to the area.
You find a clear space and take off, starting vertically upwards to establish the Home Point.
Keep the camera level. You then look around you and pick the highest object. Fly towards it, making sure you stop and hover sooner rather than later.
Look through the camera; is the object higher than it is? If so, fly vertically upwards until the camera appears level with, or just above, the top of the object.
Stop and hover. Look at the screen, especially at what height is displayed. Make a judgement call, fly upwards 5 or more metres, as shown on the indicated height displayed on the screen. Look again through the camera. Confirm you appear to be above the object.
Look directly at the aircraft and the object because this is how you start training your brain. (Get your eye in).
Fly forwards towards the object. Keep checking the view from the ground, the height displayed, and the view through the camera. Stop and hover as many times as you feel necessary.
You are not pushed for time, this is essential basic training, providing a solid foundation for successful future flights.
While hovering higher than the object, spin the aircraft. Looking through the camera, is there something else that now appears as high, or higher? Fly towards this new target to confirm your initial judgement. Repeat the process as required.
While hovering, go through the menus to set the appropriate RTH height.
Fly over these objects if you like, but please don't fly behind them, at a height lower than they are.
This procedure works on trees, hills, aerial towers, water towers, and even buildings in built up areas, if you really must.
Regards.
