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