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