What to wear with denim hot pants to stop them looking trashy?

I did the same thing! Never tried them on in the shop, and only realised just how short they were when I got home! I still made them work though - i wore mine with loose fitting tops, to avoid looking too exposed. My fave was a pretty white tunic style top. Just don't get anything too long, or it'll cover the shorts and you'll look like you're just wearing a top! With the weather getting a little colder now, I've taken to wearing them with some cool plaid shirts, or a tshirt and waistcoat combo. They'll look great with some coloured tights and boots for the winter too.