So what do I do with this ngon?

[Pamela Galli]

I am pretty sure I created an ngon.  I had this polysided empty space and filled it, and it just made one face instead of several. But I need it to be at least two faces because I will need two materials.

So I tried triangluating the face and that just messed up the mesh shape.

So I made two edges to separate the ngon into three faces.  But they just sat on top of the face, rather than actually dividing the face into multiple faces. They served no function so I deleted them.

So can someone tell me, or point me to some source that can tell me, how I am supposed to divide this ngon into faces?

[WADE1 Jya]

probably the tool you are looking for is called 'scalpel'. start from an existing point to create new points on the plane, and preferably end on an existing point or you'll make degenerates. you can use scalpel to just eyeball such cuts (unless this model requires zero tolerance engineering).

[Drongle McMahon]

Select two (or more) vertices; press "J", or Mesh->Vertices->Vertex connect.

[Pamela Galli]

Thanks to you both! 

 

Also Nacy took the file and corrected some of the mangling I had done.

[Ashasekayi Ra]

As Drongle already pointed out, you can either select two vertices and use the J hotkey to create an edge and divide the face, or you can use the knife tool. K is the hotkey for that tool. It comes in handy if you must create a lot of topology over a number of faces quickly.