As well as being an ASOS Stylist, Rachel Mae is an absolute treat on Instagram. Her feed is an absolute treasure trove of fashion inspiration and styling tips – a prime example being this pic of the lady herself in her Calvin Klein bra top. The 90s revisit, originally made cool by Kate Moss and Marky Mark, has been having a total moment through 2014 – Kendall and Poppy D have been showing us their Calvins over the summer and, for winter, it's the ultimate in cool-girl base layers. Just pair with an A-line miniskirt and chubby fur coat, a la Rachel Mae, or wear underneath a tailored jacket for sleek going-out times. Either way, you'll be onto a winner. 

Check out why it's not Christmas without a red dress, here.

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