Videos by default are displayed in order of publish date (most recently published first). You can change this default ordering, however, by doing the following:
1: On your videos page, click "Reorder videos":
2: Select "Custom ordering" and then select the collection that you would like to reorder:
3: Change the order that the videos appear inside the collection.
Please note that by default, all video collections are shown together in an "All collections" grouping. This can be turned ON/OFF on the video collections window available here: