Steaming foods and steam burns:

When you steam food you are literally cooking the food in the steam of a liquid.  Usually that liquid is water.  You could use stock such as chicken, beef or vegetable or even a white wine.  I, personally, don't think it is worth the cost for what flavor you might receive from it.

3 qt. sauce pan w/steamer insert

The idea behind steaming food is to put a small amount of liquid in a pan and bring it to a boil with the food above the liquid.  This creates the steam as long as you have a lid on the pan.  I have inserted a picture of a pan that has a steamer insert and lid to give you a visual.  Just put the food to be steamed in the insert, place it on the pan with the liquid and put the lid on top of the insert.  Now turn your burner on medium-high to high and let the liquid come to a boil.  How long you need to steam the food depends on what you are steaming and how much.  An average head of broccoli or cauliflower will take about 15 minutes once the liquid has begun to boil.  It also depends on how done you like your vegetables in this case.  If the rest of your meal is not ready when this vegetable is about done, you can just turnoff the heat source and let it sit until the rest of the meal is done.

If you don't have a pan with a steamer insert, there are steamer pieces you can buy that can be set down into the pan.  This device will keep the food above the liquid for steaming.  It is just easier to use a pan with an insert steamer pan.

Remember that you want to use caution when steaming or boiling items.  Steam burns are not fun.  If you are steaming vegetables or cooking pasta in boiling water, remember to remove the lid away from yourself.  What I mean is to leave the front of the lid on the pot or pan and lift the back of the lid first.  This way the steam or heat escapes from the back of the pan and away from you.  Now set the lid down.  If you are using a steamer insert, remove it carefully and pour the contents into a serving bowl.  For pasta, place a colander in the sink and using 2 hands lift and pour the contents of the pot into the colander.  Again, pour away from yourself and keep your face back so the steam doesn't hit you.  Remember to use hot pads or oven mitts when you do these things.

Some people like to offset the lid on the pan or pot and using both hands, hold the lid on as they pour the liquid out.  This is not the best way to remove hot liquid.  As your one arm straddles the pot it is possibly in the way of the steaming coming out the back of the pot and thus getting burned.  It would be better to pour the food and liquid into a colander in the sink than do the above.  Remember it just takes a little common sense to be safe.