i will tell you how i do it, might be better ways , im not shure.
i take a picture with my phone, send it to my photobucket , open up the picture in photobucket, then right click on the picture, click properties, copy and paste the url. come back to your new topic click on the icon that says insert image , click between the 2 brackets and then right click and paste.
hope this helps, took be about 2 yrs to figure it out