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