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