I Don't Really Have A Script... I Just Want My NPC To Wave.
It is really not that hard there are multiple youtube tutorials that tell you how to do this and there is also the wiki which is a great site for beginners.
http://wiki.roblox.com/index.php?title=Animations
^ is all you need to know how to make your character wave.
And if that does not help, then watch youtube videos!
Just make an animation with the animation editor and then make a function for it to run under a given condition like Touched or under time intervals, or If you are using pathfinding, have it wave under certain Cframes or so.