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