How to use login_destination module

Hello friends
i have one website in which i define some roles such as Teachers , Students etc
i create some pages for that
each and every role having different functionilty
which is defined in User module
now what happen whenever i login in as Teacher i will redirected to the functional page of teachers
like
Login As Teacher - Functions defined for Teachers
and i want like this
Login As Teacher - Page created by me for Teacher - Functions defined for Teachers

i found one module "login_destination" but i am unable to find that how to use that
plz help me out or if u have different way to do what i want to do
plz suggest me