Summarize the following:
Select fresh, ripe avocados from your supermarket. The flesh should indent a little when you press the skin. Insert a sharp knife near the tip of an avocado and push until you hit the pit. Slice around the pit to separate the avocado into halves. Remove the pit and scoop the flesh into a food processing container. Repeat with the remaining avocados.  If you have underripe avocados, it's best to wait until they ripen to make this dip. Underripe avocados will not process into a smooth dip. If your avocados are overripe, cut away the brown spots and use only bright green avocado meat in your dip. Squeeze the lime juice into the food processing container and spoon the yogurt on top. Process the mixture until smooth.  You can use low-fat yogurt in place of full-fat yogurt if you desire. Or try replacing the yogurt with sour cream for a different flavor. Lemon juice can be used as a substitute for the lime juice. Place the onion, pepper, salt and garlic in the food processing container. Process the ingredients until everything is smooth and well incorporated into the dip.  If you prefer an element of crunch in your dip, you can skip the step of processing these ingredients. Instead, spoon the dip into a bowl and stir in the onion, pepper, salt and garlic separately. For a spicier dip, add 1/4 teaspoon cayenne pepper and 1/2 teaspoon cumin to the mix. Spoon the dip into a serving dish and sprinkle it with cilantro. Serve with pita chips or crackers. Store extra dip covered in the refrigerator for up to two days.

Summary:
Peel and seed the avocados. Process the avocado with the lime juice and yogurt. Add the onion, pepper and spices. Garnish the dip with cilantro and serve.