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