How to set cookies in Ruby on Rails 3?

I want to store username and password in cookies.If due to some reason my page removed when i will type the URL and press enter the page will come which should come after login.I have used also session.Please help me to add cookies in my app.

I am working on the below code.

class SessionsController < ApplicationController
    def loginuser
        @users=User.authenticate(params[:users][:email], params[:users][:password])
        if @users
            session[:user_id]=@users.id
            flash[:notice]="login successfull"
            flash[:color]="valid"
            redirect_to :action => 'member',:controller => 'homes'
        else
            flash[:notice]="could not Logged in"
            flash[:color]="invalid"
            render 'member', :controller => 'homes'
        end
    end
    def removeuser
        session[:user_id] = nil
        flash[:notice]="user logged out successfully"
        flash[:color]="valid"
        redirect_to :action => 'member', :controller => 'homes'
    end
end 

Please help me to add cookies.