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