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