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