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