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)(15,22,26,21)(16,27,17,28)(18,25,20,23)(1,2)(3,4)(5,7,9,8)(6,10,12,11)(13,15)(14,21)(16,18)(17,20)(19,26)(22,24)(23,27)(25,28)(13,16,18,15,19,17,20,26)(14,21,23,28,24,22,25,27)(2,4)(13,17,18,26,19,16,20,15)(14,22,23,27,24,21,25,28)(5,8,9,7)(6,11,12,10)(13,18,19,20)(14,23,24,25)(15,16,26,17)(21,27,22,28)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.