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