how to adjust vavles on slant six??

i need help adjusting my valves, im 16 is this something i can do? to be honest i dont really know where too start. i replaced my head gasket and i was told i need to adjust the valves because it wont start... is there online directions any where or an online manuel thanksss for the help.
I park it and set the tolerance ............. You should see my /6 valve cover
Watching it run helps and no new gasket replacement is needed every 15.000 miles =D>
Do it with a gage and cold...This will get you there ..watching it you cane see why it's easy to do it while the /6 is running