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