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