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