Hex Codes in Output images?

Does anyone have any idea how to reliably add specific colors to elements in your image using hex codes? The tutorials don't really mention it, and Google AI's suggestions don't seem reliable as they mostly seem to only add coloring to your prompt output, not the image itself.

Basically, it would be something like:

subject
   {man|woman}

color
   {#8000fb|#F2450B|#78452F}

clothing
   {shirt|pants}

prompt
   a [subject] wearing a [color] [clothing]

Thanks in advance for any help!