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)(11,18)(12,20)(13,15)(14,17)(16,21)(19,23)(22,24)(3,7)(5,8)(9,11,14,13)(10,15,17,18)(12,19,21,22)(16,23,20,24)(25,26,30,34)(27,32,37,31)(28,29,33,39)(35,40,38,36)(1,2)(3,5)(4,6)(7,8)(12,21)(16,20)(19,22)(23,24)(25,27,30,37)(26,31,34,32)(28,35,33,38)(29,36,39,40)(9,12,14,21)(10,16,17,20)(11,19,13,22)(15,23,18,24)(25,27)(26,32)(28,38)(29,36)(30,37)(31,34)(33,35)(39,40)(1,3,4,7)(2,5,6,8)(9,13,14,11)(10,15,17,18)(12,19,21,22)(16,24,20,23)(25,28)(26,29)(27,35)(30,33)(31,36)(32,40)(34,39)(37,38)(1,2)(3,5)(4,6)(7,8)(9,10)(11,15)(12,16)(13,18)(14,17)(19,23)(20,21)(22,24)(25,29)(26,33)(27,36)(28,34)(30,39)(31,38)(32,35)(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.