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