2002 Sentra cylinder head

My friend was changing his sparkplugs and it broke inside the plug hole the head! He bought an easy out to get the plug out and in the process he broke the easy out pff in there too! It is a 1.8l and my question is: What is the easiest way to set the timing chain so once we remove the head we can set the timing back? When I agreed to help him I didnt know it was going to be this big of a pain!