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