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