How to prove that this graph is non-planar? 
I'm having trouble proving that the above shown graph is non planar, I think that I have to look for a subdivision of the graph $K_{3,3}$ using Kuratowski's theorem, can someone give me any tips to find this?

Consider the cycle $ADEHCF$. The edges between them form $K_{3,3}$ minus the edge $AH$; the path $ABGH$ links $A$ and $H$ without using vertices in the chosen cycle. This is a $K_{3,3}$ minor in the graph, so it is non-planar.
