Projects need a minimum of 10 screenshots if the number of worlds isn't specified, or the same number of screenshots as the project states is going to have. You need to upload screenshots to an image hosting site such as Imgur
and post the image URL in brackets like King of Eternity said. Once you've uploaded your screenshot you can get its URL by right-clicking the image and selecting "Copy Image URL" (although the option name may vary). Either way, I'm locking this thread now. If you want it unlocked PM me, or any other staff member, with the screenshots and we will unlock it.