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