Anyone who has made a paint color "mistake" will tell you, it is important to see a color at home, in different light and at different times of day to help decide if it is right for you.

One great way to accomplish this is to use paint samples.  But instead of painting the wall directly, paint a piece of foam core board (poster board works, but isn't as sturdy).  Use two coats to get a true impression of the color and move it around your room to see it in different light at different times of day.  Ace Hardware Longmont has hundreds of paint samples available, along with all of the supplies you will need to pick the right color for your project!