I've never needed any grease gun Nicholas, just a tube of lithium grease from your LBS will do. Truth is, almost any grease will do, but the trade off is between heavy grease that will last forever but create quite a lot of friction...or light grease, less friction, free'er running but will need more regular attention.
Remember, if you are servicing QR hubs, adjust the cones very slightly loose, then when you tighten the QR., it takes the play out. If you adjust them with no play, they will be too tight when you fit the wheel to the bike.
Be patient and expect to do it a few times to get it just right. Its not rocket science, after a couple goes, it gets easier and easier, its just finding the sweet spot.
Adjust, fit the wheel, see if its ok, adjust again if neccessary. A hub feels different once its on the bike, clamped up.
I always lay a clean rag out to empty the contents of your hub onto, keeps everything together.