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