You will need:
For small avacados, mix half a cup of salsa per avacado. With large avacados, mix one cup of salsa per avacado. Just squish the avacados like ripe bananas and mix it in with the salsa.
I buy my avacados at Costco so they're larger than others I've bought at other grocery stores. It's common for avacados to not be ripe when you buy them. If you leave them on the counter with a bunch of bananas, the gas released from the bananas as they ripen will help ripen the avacados within a couple days!