Well if you want to do it wothout turning the camshaft you're going to have to remove the rockers so as not to have the pistons and valves becoming overly familiar with each other.
The conventional way is to remove spark plugs ,split the chain, attach new to old, have an assistant keep pressure on the chain over the cam gear while you turn the crank.
The only problem with doing this is that you do not adress any worn gears you may have and worn gears will quickly wear out a new chain.