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