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