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