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