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