The first rule is remembering this is YOUR Home - that means don't worry about what other people think when making your home reflect the Real You.
Begin earlier in the process understanding what is available to you and what colors you want. This way, when the time comes to pick them out, you will have a shortlist rather than beginning from scratch.
Don't forget about your furniture - Whether you are bringing existing furniture or buying new, these pieces will become the focal points in your home and the base colors you choose will complement them
Go with your gut - when you can't seem to choose between two colors or finishes, just trust your instinct. It's like we all learned in school when taking a test, your first answer is usually the right one!