Stumbled across this idea at the weekend. Please don't flame me if it's terrible!
I found a cheap strappy jersey dresses in H&M:
£7.99 dress
and bought a cropped tee to go over it:
£3.99 tee
So for £12 have made one of those usually very expensive double layer nursing dresses where you pull the top up and underneath down. There were lots more colours in store than on the website so you can either have the dress and tee the same colour or in complimentary colours.
I know a while back there was a thread about hating having to wear jeans and two tops all the time so hope this helps someone now that the weather is warmer.