Ok, for images, the simplest way is this:
When you're typing away and you want to insert an image from the web (it has to be from the web, you can't upload images to here), you do the following...
type [img]
Open another internet window and go to the website containing the image you want to insert
Right click on the image and select 'Properties' (at the bottom if you're using Internet Explorer)
This will bring up the properties window. In this window there is a website address, should look something like: http://www.saskschools.ca/~gregory/anim ... charge.jpg
Select this text, right click and choose 'Copy'
Return to the Cyprus Forum window
Alongside where you typed [img] paste the web address that you have copied... it will then look like this:
[img]http://www.saskschools.ca/~gregory/animals/deer/charge.jpg
To finish, type [/img] immediately after the image address, with no spaces between
Then, hey presto, your image should appear thus: