You will need at least one cone wrench and new grease. I like "Lifu" wrenches, for about $6 shipped from eBay. Cones usually are 13-16mm and too narrow for standard wrenches. I also use the cheap Valvoline automotive grease from the auto parts store and have had no problems after using it in several hubs and bottom brackets. There is a plethora of tutorials and videos you can search for, it's a simple job.