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