Some of us may be more well versed than others in colour theory, and even so, the way we apply the theories and match our colours will remain unique. It all comes down to perception, and method you choose to apply. If you’re after an online colour wheel type tool to help you with picking the colours for your next project, these might work for you, like they did for me:
I guess this will be a post that I can add to in future, so if you find any tools let me know as well.