Narrowing down the hundreds of options of paint colours can be a daunting task. Equally once you've chosen some you like, making sure they suit your space and look good in all lights can be tricky.
A really good tip that I've picked up is NOT to paint samples directly onto your walls. We all think this is how it should be done. I know in my first ever house, I had about 6 different shades of beige dotted around my living room before I made a decision. However, painting on the walls means you only see how that colour looks in that particular part of the room and with the particular light that said part of the room receives.
Light in a doorway, near a window and in an alcove is incredibly different. The same can be said for walls in direct artificial light versus more shadowy corners. How can you know that your paint colour will look good in all environments?
It's really simple. Take your sample pots and paint up a few sheets of A4 in each colour. Then stick up the sheets in different parts of the room. Live with the sheets for a few days to see how different weather conditions affect the light and times of day, plus how they look in daylight versus artificial light. And importantly see how you respond to the colours. If you want a relaxed living space, do the colours provide a relaxed, inviting hue? Or do they become gloomy when it's an overcast day?
This trick really helps you make a good paint colour decision before spending lots of money on something that you will want to change as soon as it's up. And if that can be avoided, it's only a good thing!