"American M/D/Y date order and European D/M/Y"

I always had a heckuva time with the numerical dates. Subsequently I don't use just numbers. 12/11/2015 confuses me no end. I don't know how to interpret that. Is it December 11, 2015 or November 12, 2015? Therefore, I write it out so there's no mistake. I have come to appreciate forms that have faded DD MM YYYY symbols. Then I know.