How to boost in dead rising 2

This blog is how to boost on dead rising 2. you will need a friend and two saved files. 
me and my friend did this last night. we were working on getting 8 survivors trophy.  we fought two psychos the chef and a guy in the bathroom. we kept the survivors that we had at a restaurant that was good.  we stocked up on food.  we also gave katie some presents while we were there.
heres what you do. 
       get people to follow you
       take them to a save point in a bathroom somewhere. 
       make a new save so now the host has two save points. 
      collect survivors  
      bring survivors back to safe house 
here is a video of presents that you can give katie