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