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