If you are in an inside cabin or one without a window/verandah etc....order room service breakfast or a wake up call. It stays DARK in your cabin long after the sun is up. If you don't do this, you will sleep waaay to late! DH and I are NOT morning people and on our last 7Day Eastern there were a couple days we woke up after 11:00 a.m. not realizing it was day

luckily they were sea days and we didn't miss any shore excursions.
Also, pack half the t-shirts you think you will need. We bought t-shirts at several places and promptly wore them when we got back to the ship. It made the other t-shirts we packed just extra stuff to carry home.
As anal retentive as it sounds I also made a spread sheet that outlined what we were wearing when. This was especially helpful for DH who is clothes challenged. All he had to do was look at the sheet to know what to wear when. It also helped us keep up with which shore excursion or special dinner we were having that day.