[Plugin: Contact Form 7] Adding Drop-Down Tags

hello, i’m just a newbie to this so please forgive if i have to ask you about this problem. I already read the FAQ provided but still can’t figure it out how to.

i was trying to add a drop down tag but can’t figure it out how to understand this message.

“And, put this code into the Mail fields below
[menu-956]”

how can I add this to the Mail fields?

thank you.

screenshot: http://cubithost.com/images/wp_add_tag.png”

http://wordpress.org/extend/plugins/contact-form-7/