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