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