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