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