Excel sorting by month, day

crgregory 

If I understand what you're asking, I personally would create "helper columns" to isolate the month and the day from the full date as shown. Then base your sort on those extracted values.

(I'm assuming you want all of the Sept firsts (regardless of year) to precede any Sept seconds, regardless of year. If that's not what you're aiming to do, then please come back with a more complete description of your task.)