Like this
If you haven't done so already, find a host such as photobucket and upload the pictures you want to post to it. Then, when you are ready to post, select the option below the picture entitled
img, copy it and paste it into your post. The only thing I haven't been able to figure out as of yet is how to resize the picture (often, Forums have an option an administrator can put into effect that will limit the size of the picture in the post to save space and memory, but enable a viewer/reader to click on it to enlarge to full size).