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