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