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