Here are a few things that I have learned from years of paint stories and my own recent painting experience. Hope they help to make a happy painting experience!
#1 Color Confused? Another blog I'll talk about paint selection but definitely bring home samples of colors (either swatches or small bins of paint that you can paint a wall with to see how you feel living with it. Look at it in the morning and night. Look at it with your furniture and fluff. Does it go cold on you? Or turn another color as the light pales? Does it seem "off" or not as sunny as you wanted... Consider all this after living with the color options for at least a few days. Not just painting the walls but the ceiling, wainscoting, floors or exterior? That affects which paint you should use as well.
There are so many different paint companies so check out a big box store's selection with the big boys (Benjamin Moore, Sherwood Williams, Behr etc) and also the smaller paint companies like Farrow & Ball, CB2, Sunny's Paints, Yolo. Like beauty companies, everyone has one standout color or product and different price points. Is it a kids' playroom that you want to be no or low voc (aka eco friendly) or is it an area you want to splurge a bit? A gallon of paint can range from $25 -140; that's quite a difference.
#2 The final result is only as good as the time you (or your painters) took to prep the walls.
While painting the walls is the fun part, it's not the most important. Take everything off the walls and check the condition. Fill in the holes if you have them. Do you need to skim coat? If so, apply a thin layer of plaster to improve the wall's appearance. Some paint has primer in it but if not, put one down. It'll help the paint be its best. Also, consider your baseboards or moldings and prep them as well. Seriously, this is where people skip or get lazy but it's like a lined pair of pants versus unlined; it makes a world of difference. Factor in a day to do this part. I promise you, it'll be worth it.
#3 Hire someone. I know, I know.... it's just painting, right? But unless you are Really Meticulous, I would recommend hiring someone to get that professional look. If you can't score a painter recommendation from a reliable person, explore CraigsList which has tons of service folks. Check out their websites first and call a former client if possible. I HIGHLY recommend a face to face visit to walk through the area with the painter so they'll really be in to give you a proper estimate and foresee any roadblocks.
#4 Keep some extra paints for touch ups as accidents do happen. Also, keep the color swatch somewhere safe in case your memory fades and you want to repaint the same color.
Now, step back and enjoy your gorgeous new hue! I know that I am...