Go to the photo gallery. Upload your photo there. Once it is uploaded, there will be a window with code in it and a button to click that asks whether you want to upload the code to your clipboard. Click yes.
Next, open the forum message where you want to put your photo.
Position the cursor inside the message, and RIGHT click, select paste, and the code should be pasted into your message.
The code looks like this:
{ img }http://www.thamnophis.com/thamphotos/data//500/medium/ordinoides_head_1.jpg{ /img } ( I have changed the brackets and inserted spaces to allow you to see this)
And the resulting photo:
