How to make persistent Cookies?

How to make persistent Cookies?
 For persistent cookies, we need to add an expiration time. In the given code

//Creting a Cookie Object HttpCookie _userInfoCookies = new HttpCookie("UserInfo");

//Setting values inside it _userInfoCookies["UserName"] = "Abhijit";
_userInfoCookies["UserColor"] = "Red";
_userInfoCookies["Expire"] = "5 Days";

//Adding Expire Time of cookies _userInfoCookies.Expires = DateTime.Now.AddDays(5);

//Adding cookies to current web response Response.Cookies.Add(_userInfoCookies);