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