In "Algebraic Topology"-Hatcher the beginning of the chapter on $\Delta$-complexes shows a pictorial example of the $\Delta$-complexes of the Torus, $\mathbb{R}P^2$ and the Klein Bottle.
In a homework assignment I am asked to explicitly write out the $\Delta$-complex pertaining to the Klein Bottle.
I am really unsure as to how to think of these $\Delta$-complexes as more than the pictorial examples given in Hatcher.
I am asking for an explicit example of the Torus and hopefully seeing this example will allow me to apply it to the Klein Bottle.