If you have a picture on your own computer that you want to include in your post, click the 
Manage Attachments button on the screen where you type your post.
If you have a picture on a web site that you want to include in your post, click the 
		
		
	
	
 icon in that window and type or paste in the URL of the picture.  It will put the necessary 
img tags around the URL to make it appear in your post.  Click the 
Preview Post button and you can even see how it will come out before you click 
Submit Reply.
A third choice is to include a 
link to a picture in your post.  You can do that by clicking the 
 icon and typing or pasting in the URL of the picture.
If you need more information, such as about image formats and sizes, just ask.