Some resources that I find useful
There are some convenient conventions, but ultimately, choose a system that feels right for you and is manageable in the long run.
css tricksAlthough not its main purpose, OKLCH color picker and converter is a very convenient tool for creating color palettes. My website theme is teal and pink. In OKLCH, this converts to hue values of 180 and 0 respectively. From there, I just had to choose a chroma value and change lightness to create my palette.
OKLCH color picker