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