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