Soft walls, color in the textiles
An easy way to get it right is to paint the walls a soft shade and bring the bolder colors into bedding, curtains, pillows and rugs. Textiles are easy to swap if you get tired of them; paint, not so much.
Check which way the window faces
A room that gets little light or cool light (north-facing rooms in the Northern Hemisphere) looks better in warm shades like cream or soft terracotta. If it gets lots of sun, grayish blues and greens cool it down visually.
Test the paint on the wall
Paint large samples, at least 2 feet square, on two different walls and look at them by day and at night under your lamps. The color on the paint chip almost always looks darker and more saturated once it covers the whole room.