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