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