Hi Avril - welcome to the website! Lovely to meet you 
Using smileys is quite easy - just click on the little button that looks like a yellow smiley face, just above the bit where you type your message.You can then choose from lots of different ones. When the smiley first appears in your message it will look like lots of symbols (for example, the one we've used up there looks like [ < : o ) ] ) but don't worry - it'll look fine after you submit your message.