Here is what I follow and will advise others to follow:
I always avoid:
- Going in a big group of people for bird watching as that scares the birds away.
- Making any kind of noise.
- Making sudden or rapid movements near the birds.
- Getting too close to the birds. That disturbs them. For pictures, I use a long lense.
- Carrying my mobile. If I do need to carry my mobile, I atleast ensure it is on the silent mode if not switched off. A mobile going off while there are birds around can spoil the moment.
- Luring birds through recorded bird sounds. It can trick them into thinking that there could be a mate, a rival or an intruder.
- Luring birds with baits.
- Disturbing the habitat.
- Littering the area.
- Wearing bright colored clothes.
- Using camera flash.
- Touching / disturbing any nests.
- Being impatient.
Remember that the best bird watching / photography experience is when the birds are totally undisturbed in their natural habitat. I have got some of my best pictures like that.