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