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