If you're on a PC, you scroll down to 'manage attachments' and upload an image of your chart. If you're on a phone, include a link in your post (to your chart) on a free, image-hosting site like imgur.
Just FYI it's a little bit much to ask for people to go through the rigmarole of casting your chart etc., you know.. especially if you're not a known contributor and there's no guarantee you'll ever come back with feedback or continue to contribute to the forum yourself. Just saying