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