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