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