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