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