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