A very important element is missing from your day today, and you need to make sure you that you find it before the end of the day. Have you left a fun person off the guest list? Forgotten to double check your work at school? You need to slow down and think things through in order to remind yourself what it is you have forgotten. Get a friend in on the chase with you -- ask them if they know what you're trying to remember. If they don't, they may be able to help jog your memory.