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