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