One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,8)(4,6)(5,7)(9,10,13,16)(11,17,19,14)(12,20,21,15)(18,22,24,23)(25,26,32,36)(27,33,29,34)(28,38,39,40)(30,35,31,37)(3,4)(6,8)(9,11)(10,14)(12,18)(13,19)(15,22)(16,17)(20,23)(21,24)(25,27)(26,33)(28,35)(29,32)(30,40)(31,38)(34,36)(37,39) involution — undirected(1,3,5,4)(2,6,7,8)(25,28,30,33,32,39,31,34)(26,27,37,40,36,29,35,38)(9,12,13,21)(10,15,16,20)(11,18,19,24)(14,22,17,23)(25,29,32,27)(26,34,36,33)(28,35,39,37)(30,38,31,40)(1,4,5,3)(2,6,7,8)(11,19)(14,17)(18,24)(22,23)(25,30,32,31)(26,35,36,37)(27,38,29,40)(28,33,39,34)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.