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