How do you write the date correctly in English?

Well, people do it differently, but the main difference from some European styles is that we list the month, then the day, then the year. So, you would write November 9, 2007 or 11/9/07 usually. Sometimes you need a 4 digit year for software, or a teacher asks for a certain style in a paper, or you need to include the day of the week for instance... but either of those work if you are just putting the date at the top of a letter. The written-out month is preferred in formal writing.

________

It depends on where you live and who you work for.

In the US it's usually mm/dd/yy or mm/dd/yyyy

in the military it's dd Month yyyy

in Europe they do dd/mm/yy

So go with the local flow