OK .... then sign in on the website via your browser and it should work the same way a computer does. Above this message box there should be some pads with various icons, words, letters, smiley, etc.
Just to the right of the globe with the red X there's a "picture frame" .... click on that and follow the prompts.
You also might want to go to the TESTING FORUM and experiment posting there, first. Then you can play around and make mistakes & then edit them out and correct them until you get the results you want. Then you can either come back on this forum (or any other forum you choose) and either use the same steps .... OR you can always just copy/paste from the Test Forum post to any other forum post or thread. Once your pics are on the site, they're hosted here and you don't need to pay a hosting site to store them for you.
If your pics are ALREADY on a hosting site .... you just have to copy/paste off of it to post them here.
IF you use a phone to take the pics, then download them to your iPad (or computer) ... best to try the Test Forum posting out, first, because some phone pics will come out sideways (1/4 turn to the left) because the orientation code of those phone pics is not picked up by this site and the site will turn the pics to the Landscape orientation. Don't know about an iPad/iPhone, but my Android phone has to be turned 1/4 turn to the right when I take pics I want to post here, in order for them to come out right. And even turning them in my computer files doesn't work, because turning them in the computer files doesn't really change the orientation code.
If this doesn't work, you may want to send a PM to Slab and ask him how he did/does it from his iPad. Don't know if he still uses it, or not, but I believe he did at one time.