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