Ah the good old days of getting the shade cards from the decorating shop and standing in various spots around the room to check lighting – direct sunlight and from the one overhead light bulb . . .  then before we were able to buy those tiny tester pots, we’d take a chance on the colour and buy a tin.  So often you’d hear Dad enthusiastically start his next project, to be shortly followed by a loud shriek of anger from Mother.   Oh how many well intentioned home decorating project were suddenly and dramatically paused with only a few brush strokes.  If  Mother didn’t like it, there was always trouble for the rest of the day / week / month.   It can be quite expensive buying several little tester pots but if a specific shade is wanted, this is a good way to achieve it.  Although some decorating shops of course will mix your exact colour.  Take a sample of the shade – say a piece of fabric or similar, they will do some whizz kid stuff with the machine and soon your paint comes out exactly the shade.