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