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