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