Layering prints is something that a lot of us approach with caution, myself included. I do feel that mixed prints often land either end of a scale - really cool, or really awful and I've experienced both myself.
I've spoken a little recently about the importance of trying pieces on before you make a judgement. As we all know, things can look monumentally different on a human body to how they look on a hanger, and the thing about mixing prints, in my humble opinion, is that there aren't any rules; there isn't a special formula or cheat sheet. Bold prints can work with subtle prints, big with small and monochrome with colour - and sometimes, two prints you'd think match perfectly can look terrible on. You simply have to experiment, and when it works, you'll just know (& when it doesn't work you will also definitely know...) - which is what makes mixing prints so fun!
To further demonstrate the randomness of print-mixing success, this outfit was an accident. I'd been trying on some new pieces and had rather unceremoniously (and slobbishly) chucked a couple of 'keep' items over my coat rail; a geo printed shirt and a pair of black and white pinstripe trousers - which had landed atop of a ruby red coat from COS. Draped over the end of the rail was my new no.1 faux fur accessory - a striped stole from Reiss. Somehow, it all worked - and of course it's fine if you disagree, as after all personal style is all in the name - it's personal!