You can easily share photos on our BMW 4-Series forums.
First upload your images to any photo sharing site like Photobucket. For those unfamiliar with this technique, I recommend Photobucket.com, as this photo sharing service will display an image URL address adjacent to the image that you can use to share the photo.
In the forum's post editor is a button
you can select. When prompted, paste the URL address of the image and the system will then encapsulate the image with the proper code tags so that the image will appear in your post.