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