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