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