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