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