Look at colour samples in the room or space it is intended for. Colour is light dependent, influenced by many factors and very subjective.
I match colours from most manufacturer’s colour systems to the paint system I use. So no problem, go colour hunting.
One way of avoiding colour mishaps is to choose a colour from a Sherwin Williams colour brochure. Designers have picked these colours and used them extensively. They look great!
Pick what you like
Are you choosing a colour purely for visual effect or are you trying to create a certain feel? What colour does the space feel like to you?
Avoid choosing colours in an attempt to compensate. Pick the colour you like. Avoid picking a related shade (hue) because you think the colour is too dark, too light or too whatever.
You might like a colour but there is something not right about it in the space. Try changing the lighting and/or accessories in the space. Does the room need brighter or softer bulbs? Would a floor lamp or table lamp help? What options are available to give you what you’re really after. Decorating is a matter of numerous factors including the colour and sheen of paint.
Use an eggshell sheen for walls and either semi-gloss or pearl for trim. Pearl is not as shiny as semi-gloss but shinier than eggshell providing sufficient contrast.
Take your vent covers from drab to fab from the Lighter Side of Real Estate.
Baseboards look classier without 1/4″ round. You can replace the 1/4″ round with a square or rectangular piece of wood and paint it to match the rest of the baseboard.