Yo tambien vs. A mi tambien

Yo tambien vs. A mi tambien
 

I've googled and found a few different ways to explain this but nothing has been good for me.

Does anyone know a simple rule to apply when knowing when to correctly use:

Yo tambien vs. A mi tambien / tampoco


TIA

If the statement you're responding to contains a subject pronoun (omitted or not), you likewise use a subject pronoun, like 'yo'.
If the statement contains an indirect object pronoun, you respond with an indirect object pronoun, like 'a mí'.

Quiero ir al super.
- Yo también.

No quiero ir al super.
- Yo tampoco.

Me gusta ir de compras.
- A mí también.

No me gusta ir de compras.
- A mí tampoco.

Gracias, Rusty.