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