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