There are a couple of things you need first:
1) To be logged into this website. This does not mean you need to be a WTC member, just that you have created an account here, and are logged in.
2) To have a photo uploaded online on another website (WTC does not host photos for members or non-members). You can use a free website like Flickr, Shutterfly, Photobucket, or any other to actually upload the photos online. General rule of thumb; if you can see a picture in a web browser, you can embed it in the forums.
Once you've gotten that taken care of, here are the steps to display a photo on these forums:
1) On the photo you want to embed, Right-Click on the image, and select Properties

2) Highlight & Copy the Address/URL of the image onto your clipboard

3) Create a new thread on our Forums (or reply to another thread)

4) Fill in a title of the new thread, and then click the Insert Image button

5) Paste the image Address / URL into the URL textbox on the window that pops up

6) Submit the image

7) Submit the post

8) Hopefully, enjoy the finished product!

9) Leave comments on other people's images. They took the time to upload & display the photo. Let them know their work is appreciated!