One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,4)(5,6,10,7)(8,12,9,11)(13,14)(15,18)(16,19)(17,20)(21,24)(22,25)(23,27)(26,28)(6,11)(7,12)(8,9)(13,15)(14,18)(16,21)(17,22)(19,26)(20,25)(23,28)(24,27) involution — undirected(2,4)(5,7)(6,10)(8,12)(9,11)(13,16)(14,19)(15,21)(17,23)(18,24)(20,27)(22,28)(25,26) involution — undirected(5,8,10,9)(6,11,7,12)(15,22)(18,25)(21,28)(24,26)A 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.