I belive my truck needs new valve stem seals because each morning when i start my truck it will have blue smoke come out the exhaust for like a minute. After that it will be thenormal exhaust color.

How do i change these; what are the procedures. What tools are required? PLEASE help

 

sorry i forgot to list: its a 91 b2200 with 158k miles. It runs great just the blue smoke, and i need to add a quart once a month.