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