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