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