Sooooo, I’ll going to try my best to share a bit of my perspective. I ask for a bit of forgiveness from the crowd, perspective is hard to get across in a message 
Take as much, or as little from this as you like.
If I might, I would like to start with a story…
A young lad walks out of school, thinking maths/sciences are stupid. He passes all his classes, but never really learns anything. Feeling as though it’s all figured out already, thinking they are painfully boring, and he thinks little of those worlds. It must be the brainiacs that find the joy in understand these things 
This story is a tragedy… because they’re both F–kin awesome!
Color is also, F’n awesome.
So, why?
It’s one of the few tools, that lets you play in the world of feels. The only thing that’s comparable is musical notes (C,D, Major, Minors etc).
So, how do I use color?
We play with it. Say we start arting, right here, right now! We have the intent to make ourselves feel a bit sad. So, that’s what we will be trying to capture.
What makes us sad? Does a bright sunny day, make us sad?
no…
What about a bunch-O really bright primary colors, just exploding all over the place???
Well that makes me feel like I’m at a party, so no.
Okay then, lets go the opposite way! Dark, and muddy?
Better, but the type of sad we’re after tonight is something like dropping your fav sandwich… on the sidewalk… right as your about to take the first bite… you know it’s gone forever…
I hope you can understand why we can’t just go with dark and muddy colors here, it’s just not the right feels. Think streets you’ve been on before, that’s our background color. Let us juxtapose that, against all the vibrant colors of the mouth watering sandwich innards. We’re drawing focus towards the crime scene. Then we need to think about the lighting.
What time of the day would you crave the perfect sandwich? Like REALLY crave a good sandwich. none of this “of ever day at 6” crap. It has to be THAT day. Not the worst day ever, but just one of those days. Maybe at the end of a long day, working hard on something I don’t really enjoy doing. or worse? you chose.
What about Twilight lighting? It can be very moody?
Ya, but this is not about a beautiful sunset, it’s about the sorrow of a lost friend, who deserved a better ending. So it’s just dark out, and your just looking down at the concrete sidewalk. The only light is cast from dim street light. No real moon out tonight. So it becomes a bluey-purpleish-grey background, with the crazy red’s of the tomatoes and greens of the veg. All muted out by that weird yellow light. A sad song plays from a radio close by. RIP BLT.
We just happen to have landed on a perfect yellow/orange/blue/purple color palette. How? There was no plan for that?!?!
Conclusion
Don’t try to follow all the rules, just follow feelings. To really wield color, you go by feel. Put something down, ask how you feel about it, repeat.
I’ve read, listened, and generally stewed in a lot of information about color theory, for years now ><. I’ve used little of what I’ve learned. Some technical information about color has been cool. For instance, if you’ve ever seen sunlight hit a colored wall. You may have noticed how much that walls color fills the room. Or you might be curious how matte colors, vs shiney colors work (Hint it has to do with the objects surface rough/smoothness). There’s lots of fun to be had discovering all the odd things that make things look like things, but you don’t need to stress about them, they’re more like curiosities.
I hope this helps,
