Layering is key in this look, so try a basic loose tee in nude, grey, black or white (Zara, Topshop, H&M, Primark) under a Breton stripe top, which every girl should own. Its hard to recommend shops for these, as everyone likes a different style. I have 2 however - A short sleeved tee from H&M and a long sleeved classic french vintage one. Complete this look with skinny jeans, plain boots or plimsolls, long miss-matched necklaces and a couple of bangles.
For cooler weather a military style coat is the essential cover-up. Wear with a simple skirt, black opaques and brogues.
In the summer opt for ripped denim hot-pants an striped tops or shirts, semi-tucked in. Add ballet pumps and a bright beach bag for days tomboy fun in the sun.
Alexa Chung is pretty much the saint of the Breton stripe top, so if you're trying to emulate her style then its a absolute essential. It can be so tricky to find the perfect one, so I've helped you out a bit - I love this Jack Wills version of the classic, its loose, stylish and distinctly Alexa Chung:Its in the Jack Wills seasonal sale now, for £39.
Skinny Jeans are another wardrobe essential, and key to the Alexa look. If you don't already own a pair head to Toppers and snap up these beauties:
For the military coat try Zara, or Primark's wonderful new collection. Topshop also have some nice versions and if you're shopping with no budget then Miu-Miu, Burburry and MaxMara are the coat Meccas.
For a night on the town stay with the cool vibe, just dress it up a little with a Uniqlo grey marl jersey skirt, ballet pumps (Office, Faith etc.), a blazer (Another Alexa essential, try Zara and Ralph Lauren) and head to Gap and snap up one of their new silk slouchy tees for the finishing touch of laid-back luxe.
Skirt - £19.99 at Uniqlo
To add an individual touch add a few different necklaces, bangles and rings to your look, but be careful not to over do it or you will look like you tried to hard. The aim is to look like you couldn't care less, but still be utterly fabulous!