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