I'm copying a fine art youtuber and it's working. Bright primary colours are turning into muted subtle ones. I don't have a colour wheel and am not swatching but they look close. Mixing little dabs of paint with a toothpick in a paper bowl works too but is pretty awkward. (No palette knife.)
Ps. Melbcat got very excited when I opened the paint tubes. Sounds of plastic? A bowl. Something being opened. 'What are we eating?' To be fair to her I am drinking something from a cup that looks the same as the paint water cup so may actually commit the classic blunder