I posted a method a while ago for a potter Susan, which I've just looked out, which might help. Obviously, you're starting by taking a photo with the camera,,not screenshotting something, so ignore that bit.
'The way I've done it on an iPad is to screen shot the picture or page I want to post ( hold down on/off button and then press button at centre bottom). Then I click 'post reply' on the forum thread, then the 'upload a file' next to it. This opens a box saying 'select file' , click that and it gives you options, one of which is 'photo library' . Click that, and it takes you to your photos and screen shots, and you can select the image you want. It attaches it, and asks you if you want a thumbnail or a full image. (I always go for full image).'