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