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