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