How do you put a new timing belt on properly on a 1991 Nissan Maxima?

un less you own a timing gun , lots of good tools, a manual ,and are very under standing of timing gun opperation.i won't not concider doing this job yourself.if your going to replace it....i would stongly recomend replacing a 3 fan belts.an the water pump cause there all there and in your way....see a mechanic it will cost you less in the long run......all the best .......buddy mack. all 3 fan beltsand the water pump...corrections