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