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)(11,12)(13,21)(14,18)(15,16)(17,24)(19,22)(20,23)(25,26,30,33)(27,31,34,38)(28,29,32,37)(35,36,39,40)(2,4)(7,8)(9,11,15,19)(10,12,16,22)(13,23,24,14)(17,18,21,20)(27,34)(31,38)(35,39)(36,40)(1,3,6,5)(2,7,4,8)(10,16)(11,19)(13,24)(18,20)(25,27,30,34)(26,31,33,38)(28,35,32,39)(29,36,37,40)(1,2,6,4)(3,7,5,8)(9,12)(10,11)(13,20)(14,17)(15,22)(16,19)(18,24)(21,23)(25,28)(26,29)(27,35)(30,32)(31,36)(33,37)(34,39)(38,40)(1,4,6,2)(3,7,5,8)(9,13)(10,17)(11,14)(12,20)(15,24)(16,21)(18,22)(19,23)(25,27)(26,31)(28,35)(29,36)(30,34)(32,39)(33,38)(37,40)(1,5,6,3)(2,7,4,8)(9,14)(10,18)(11,13)(12,21)(15,23)(16,20)(17,22)(19,24)(25,29)(26,32)(27,36)(28,33)(30,37)(31,39)(34,40)(35,38)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.