"Leave nothing but footprints, take nothing but photographs."
Clichéd but essential. As more people seek the solace of the outdoors, the pressure on popular areas like those around Cape Town is becoming intense: Litter, erosion, plant damage, fires - don't do it, don't cause it. Stay on established paths and roads. Taking short-cuts where there are no paths, especially on sloping ground, damages the plants and leads to erosion. Cape conditions and vegetation are such that recovery is slow. Please protect the fynbos and stay on the paths.
Teach your kids to look after the environment.
Be prepared to pick up other people's litter. There will always be people who litter, but by pulling together, those who care can control the impact.
Clean up after your dog. Your dog, your responsibility. It may be bio-degradable, but it doesn't work on other peoples shoes and car-mats.