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