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