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