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