Cover Letter Advice?

Can anyone tell me roughly what needs to be included in a cover letter for a working holiday visa?

I'm trying to write one as well.
From what I get, I think it's pretty much like a work cover letter, yet more detailed towards reasons to live in France.
Try finding details about France, and specific places you would like to visit.
Not sure if this helps, but it's pretty much what I am going to do.

I've just gone through this process. What I recommend is to choose 2-3 reasons why moving to France would be beneficial to you. It doesn't have to be overly wordy - just has to show you are sincere and realistic about y our goals going in.