ESD protection of input pin with Transsorb

Hi,

I am working on a little controlpanel with a 12F629 pic.

I want to protect the input ports from ESD and I think that the best way to do that is to use a transient diode.

But how do you use them right?

I have attached a small diagram that shows what I think is the right way.
So please take a look on the attachment and give me your comments.

By the way, should I use a Unipolar or a Bipolar diode?
My own guess is to use a unipolar, but I'm not sure.

Gert K.