Unnatural hair colors on Afro/curly mix hair

Being 31 is no barrier to fun hair colours, many of us here are older, myself included.
You will need to bleach for the turquoise to show, some  hair types bleach better than others. Afro hair can be quite brittle and dry so if combined with fine strands it could become very fragile and frizzy when bleached. Thicker strands tend to be more resilient. The best way to know for certain is to bleach a strand test. If you would be happy with a darker turquoise/teal shade you can get away with only bleaching to a gold rather than blonde.

Pfft, 31, you're a baby still! I used to know a woman of 65 who dyed her hair a different bright colour every week! I'm almost 42 and don't care now if I'm "too old".

"Would it look soft" is a phrase I'm not sure I've heard before, so I'm not entirely sure what you mean by that.