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