Popup / Tooltip to keep informed user's use of cookies

Question

hello

I created an web application with asp.net mvc 4 razor with Visual studio 13. This one uses cookies. So I want to create a small window as a popup ("""which is just a DIV placed anywhere on my page and have a close button to disappear this DIV""") that appears that once a user to tell him that my site uses cookies.

Please can you help me.

Thank you.