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