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