how to reset the timing

This is from ProDemand.com.

It is common practice to replace the timing belt at the same time. If you do not, mark where the tensioner pulley's bracket is now, then be sure it is at least that tight when you are done. Regardless if the belt is new or not, do not rely on just spring tension to pull the tensioner pulley tight. They often stick resulting in a loose belt. The symptom will be an elusive overheating problem due to a slipping water pump pulley. Turn the crankshaft by hand two revolutions, then recheck the timing marks and double-check the belt tension. Always turn the crank in the normal direction. That will place any belt slack on the tensioner side.