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