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