How Can I Get Soft, Light, and Loose Curls If I Have Really Thick and Crazy Big Curls?

I'd really like to achieve something like this:





But my hair is so stubborn and I can't seem to figure it out. It's basically really thick and very curly. I've tried getting it thinned but that just made it worse!

It would be super helpful if you could give me some tips on how to get it cut so it isn't so thick, and how to get from insane big curly hair to something along the lines of the picture I have sent.

Thank you!