Speaking of cleanliness, on previous occasions, the end result of all this is clean colours.
There is much to be said about colour mixing, that I could never cover on the Internet.
Try keeping each colour you mix to a minimum of colours from your pallet. The more variety of colours from your pallet that you mix, the closer you get to ‘Mud’. That is dirty in colour.
Ask the question of yourself very clearly - "Do I want a hot colour or a cold colour"?
If it is neither one nor the other it not only loses a great opportunity to contrast against it but it also is in danger of being boring at best, and muddy at worst.
If you decide on a cold colour go easy on the mixing of hot colours. If you want a hot colour mix, then don’t put large quantities of blues into the mix.
Of course there are always exceptions to every rule, but I have found the ‘Hot & Cold’ decision to be pivotal