Steaming vegetables is a great way to preserve their texture and their nutrition and it won't end in a soggy, gross side dish with your dinner. If you don't have a steamer though and you're in a pinch, grab a plate and a roll of aluminium foil. This trick from Food52 will get you steaming in no time.
It's pretty simple: just take out a few lengths of aluminium foil and ball it up. Put them at the bottom of a pot that's larger than the plate you want to steam the vegetables on. Add water to the pot just so the aluminium foil balls are covered (or a little less than covered). Put the plate with the veggies on top, and turn on the heat. That's all there is to it: a quick, hacked-together steamer.
Food52 also notes that you could get the same effect with a mesh strainer laid across the rim of the pot -- assuming you have one of those strainers with a long handle and a short hook on the other side so it won't fall into the pot.
How to Hack a Steamer [Food52]