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