How does the arrangement of graphite allow a pencil to make a mark

Graphite is one of the allotropes of carbon. Unlike diamond, graphite is an electrical conductor, and can be used, for instance, as the material in the electrodes of an electrical arc lamp. Graphite holds the distinction of being the most stable form of solid carbon ever discovered. It may be considered to be the highest grade of coal, just above anthracite, although it is not normally used as fuel because it is hard to ignite

Graphite is one of the allotropes of carbon. Unlike diamond, graphite is an electrical conductor, and can be used, for instance, as the material in the electrodes of an electrical arc lamp. 

Its the second one nonmetals are moldable and easily shaped 

Not a  mixture of two common elements that can be separated by physical means.