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