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