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