I use my small crock-pot for this, only because I just decided to purchase 5 bulbs for my endeavor.
I could have done more, but ultimately you don't want to keep the garlic in the refrigerator for too long once you have made these.
Slice the tops off of the bulbs, not too deep, but just enough to expose the garlic cloves.
In your crock-pot, you have two choices, you can either place the garlic bulbs face down, so the cloves are submerged in the extra virgin olive oil, or you can place them face down, but every so often you will need to baste them with the olive oil.
I chose to place my face down in the olive oil.
Pour in enough olive oil to cover the bulbs about half way up.
Do not submerge them.
Set the crock-pot to medium-low until the oil just starts to simmer, then turn it down to low.