When viewing your repository or repositories of groups you are an organizer in, you can change the order of your files and folders and move files and folders inside other ones (or move ones that are currently inside out).
To change the order of a file or folder, click the dots on to the left of the folder or file's name that you're interested in. Dragging while clicking will move the file or folder up and down. A gray outline will show you where the file will appear if you drop it at that point. Drop your file or folder to save it in its new order.
You can drop a file or folder onto a target folder to put that file or folder inside the target. As you're dragging, move your cursor slightly to the right and look for an indented gray box under your target folder. Dropping there will move whatever you were dragging inside that folder.
Similarly, you can move a file or folder up in the hierarchy and out of the current folder it resides in by dragging your file or folder up to the top of the list and looking for the indented gray box underneath the "Up One Level" link. Dropping a file or folder there will move it up one level.
After you drag and drop a file or folder up or down a level, it will appear at the bottom of the list in its new level.