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