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