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