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