One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,4)(5,6,10,7)(8,11,9,12)(13,14,19,16)(15,22,23,28)(17,27,18,21)(20,25,26,24)(6,11)(7,12)(8,9)(13,15)(14,20)(16,26)(17,25)(18,24)(19,23)(21,28)(22,27) involution — undirected(2,4)(5,7,10,6)(8,12,9,11)(13,16,19,14)(15,22,23,28)(17,27,18,21)(20,24,26,25)(15,23)(20,26)(22,28)(24,25) involution — undirectedA Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.