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