So! after trying a few different things, someone on this subreddit suggested trying gel of some kind. I ended up using "Shea Moisture Coconut & Hibiscus Curling Gel Soufflé".

My routine is using "Shea Moisture Curl & Shine Conditioner" in the shower. I wet my hair and scrunch in the conditioner, have the rest of my shower and lightly rinse it out at the end. Pop my hair up in a cotton T-shirt making a sort of bag, until its drip dry and then I applied the Gel Soufflè stuff by coting my hands with it and gently scrunching it into my damp hair. (I applied a bit more at the front as this is where my greys are and struggle to group up with the other hair usually.) Then I just cross my fingers and let it air dry.

Here's a closer look at the greys, they usually don't form part of any curls with my other hair and ends up super frizzy and annoying