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