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