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