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