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