To listen, you need to absorb knowledge from the person you're conversing with. Practice emptying your mind by going into quiet and relaxing for 5 minutes before a conversation.
2 - Process
The easier part. Once knowledge is acquired it can be processed more efficiently. I feel most people are really good at processing but the absorbing part is a challenge at first, for our minds are full of judgments, opinions, rebuttals, all types of stuff, and we can't absorb with an already saturated mind.