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