My true introduction to the world of interior decorating (of rooms, not the body) was via my mother -in-law.
She are very particular about choosing the colours of walls etc in and outside her new house. This is about 18years ago.
I think that accounting for both inside and outside colours there were 110 sample colours tried out.
One side of pieces of cardboard about 80 by 80 cm were first coated with a primer/undercoat and then 2 coats of the sample paint and placed in various positions within a room or on outside wall so that the colour could be judged in all matter of lighting and positions. Muggins here was the 'volunteer artist/painter'.
The ceilings were already painted a flat soft-white colour although I have been in houses where the ceilings were a pink colour, supposedly to give people's faces a rosier appearance.
My mother-in-law was also definite about lighting, none of these cool-white light globes which she said made people look like they were in a morgue. Warm colour lighting only.
The end result:
The colours that appealed most were ones that reminded one of food in some way, or elicited a gustatory (taste) and./or olfactory (aroma) response or memory.
Although, not saying that the walls had to be an avocado green or lemon squash yellow.
The colours were more subtle and thus less likely for people to tire of them: peaches/apricots, yellow creams, tantalising cool oranges. And the outside: reminiscent of the American brownstone tradition. Guess what the neighbours called the house:
The chocolate house !!
Several years ago my wife and I wished to repaint the main bedroom. But the duvet cover ,a grey-green silk number, was to be part of the colour scheme as well as some wood features, with an easterly aspect and a preference for darkish colour carpet.
We employed the services of an interior decorator who came up with a colour scheme which we had not envisaged. I think one thinks of past colour schemes and tried to 'fit or squeeze' them into the new room and cannot make things work.
An independent opinion saves lots of later grief and regret.
Result: a dark black-grey carpet, brightish lemony skirting board, doors and architraves, a deep yellow gold on the wall, slightly coolish flat white ceiling and a feature wall of rushgreen. Of course the fact that Aussie sporting colours are yellow and green had nothing to do with it. The colours have 'food-appeal' without making one wish to raid the fridge.
Colours are so personal but please consider the 'food connection"!!