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