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