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)(15,17)(16,19)(18,20)(21,22,26,28)(23,24,25,27)(2,3)(13,14,16,19)(15,18,20,17)(21,23,26,25)(22,24,28,27)(13,15)(14,17)(16,20)(18,19)(21,24,26,27)(22,23,28,25)(2,3)(5,6)(7,10)(8,9)(11,12)(13,15)(14,18)(16,20)(17,19)(21,22)(23,24)(25,27)(26,28) involution — undirected(1,3,4,2)(5,7,8,11)(6,10,9,12)(13,14)(15,17)(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.