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