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