Air Bubbles on Interfacing

I was asked an interesting question about interfacing. 
How do you prevent air bubbles when ironing on to fabric?

Some of you may know or not, so this was my answer. 
First, I heat my ironing board by ironing on it.
Then lay my interfacing sticky side up on the hot area and rub it, till
all of the area is hot and the folds are less and is laying as flat as it will get.
Then I lay my fabric piece down. I DO NOT IRON, I press, starting in the left hand corner, and pick up iron and move half an iron length, till I get to the other side.
Go back to the left corner and continue until I am done.
This works for me. And take your time to press,
If there are any tips you have let us know.