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