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