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