I'm trying to prove the graphs above are isomorphic to each other but I'm struggling with defining the bijection from the vertex set of F to the vertex set of G, ie
$\phi(a) = ? $ , $\phi(b) = ?$ , ..., $\phi(e) = ?$, $ \phi(1) = ?$, ..., $ \phi(4) = ?$
Both graphs are 3-regular and so I couldn't use the degrees of the vertices to help determine this. What's a simple way of determining an appropriate mapping?