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