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