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