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)(13,14,18,17)(15,19,22,26)(16,23,25,20)(21,24,28,27)(1,2,4,3)(5,6)(7,10)(8,9)(11,12)(13,15,18,22)(14,19,17,26)(16,24,25,27)(20,21,23,28)(6,9)(10,11)(13,14,18,17)(15,19,22,26)(16,20,25,23)(21,27,28,24)(5,7,8,12)(6,10,9,11)(13,16,18,25)(14,20,17,23)(15,21,22,28)(19,27,26,24)(1,3,4,2)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.