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