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