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