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