There's a great website - http://splasho.com/upgoer5/halloffame.php - which encourages us to write about complex ideas in simple terms, using the 1000 most common words.
It's great, but challenging.
I put up my ideas about what I do - clinical psychology and mental health - you can read it below, and at http://tinyurl.com/b3s5lfx
This is what I said:
"I try to help people who are sad or scared.
There are all kinds of reasons why people are sad or scared, but I am interested in the things that have happened to people.
I try to work out how the things that have happened to people might have changed the way they think about themselves, think about other people, think about how the world works or what might happen next.
If some very bad things have happened to you, you will probably think that bad things will happen again. If people have hurt you in the past, you will probably be scared that it might happen again. Some people get so sad or scared that they need help. Some people get so sad or scared that it changes the way their brains work. When people are very sad or scared, they sometimes ask doctors to help them. But this doesn't really work very well, and can cause as many problems as it helps.
I try to help people by understanding why the bad things that happen to us can make us feel sad and scared. I then talk to people to try to help them understand that they can do lots of things to help themselves. Most people can find better ways to help themselves. Usually, that happens when they come to understand that they can think about the world in different ways, and that talking to other people is the best way to learn how to think in new and different ways."
Have a look, look at other people's ideas, and perhaps try your own.