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