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