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