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