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