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