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