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