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