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