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