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