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