Need Help With mapping (AI-mesh)

[Night1]

Hey, i have a problem with mapping: I know nearly everything, but i have a problem with editing an AI-mesh. I only can make a complet new AI-mesh, and moove these Vertices. But i can't edit new Vertices with edges and faces. Can anybody tell me how to that?
Geetings: Night

[-Perception-]

Select an edge and extrude it. Thats the function youre looking for if I understood your post correctly.

[Night1]

yes, thanks