I did this assignment a long time ago. The assignment was to record your self as your character and it had to be with another character. It has to be 2 minutes long.
Step 1: Write a script of the conversation that your character and another character are going to have. (be sassy, have fun with the words, and maybe even be dirty). The more chemistry the characters have the better.
Step 2: Once you have the script, record your voices and make sure you do not sound like a robot and be playful in the recording process because it will sound good when it has been put together.
Step 3: If you have audacity this goes a lot more smoothly. Put all of the recordings into Audacity and listen to then, if there are any noises that do not belong then get rid of them by using the cut button. If you have two separate sounds that you need to splice, highlight what you need and use the file button and go down to export selected audio. This will allow you to only use that much of what you need.
Step 4: Add in sounds, such as, a beep, that lets the audience know that someone is going to leave a message. Detail the message with sounds that someone would think belongs in a message that was recorded.
Step 5: Once you have spliced it together, listen to your recording and made sure it sounds good, you can now listen to the final product to make sure every detail has been put into place. Details are important because it gives the creator credibility and it makes for a more convincing conversation between 2 or more characters.