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