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