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