1. Drain the coolant via drain plug or pull off radiator hose into clean drain pan.
2. Loosen the bolts on the water pump pulley and then take off the serpentine belt.
3. You should then be able to access the water pump bolts, pull it off and clean the gasket mating service, install with a new pump and gasket. Tighten to the proper spec - probably about 20 ft lb. Make sure everything is put back together, torqued properly, put new 50/50 coolant in and check for leaks. Run it and make sure air is out of system and still no leaks.
Pretty straight forward on those 3.0 engines, unless yours is the 3.8...?
---Dale in Southern Idaho -- Done Right Automotive Service