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