This achievement occurs during Episode 5 - Outatime
Once inside the Expo have Marty do the following:
• Walk over the the large glass building.
• Interact with House of the Future Turnstile
• Interact with Console.
• Interact with Red Button.
• Interact with Console.
• Interact with Blue Button.
• Interact with Console.
• Interact with Green Button.
• Dialog (Console): "Phone Booth of the Future"
• Dialog (Trixie): "Carl Sagan"
• Dialog (Trixie): "Can I talk to Edna"
•
to exit.
• Interact with Console.
• Interact with Phone Button.
• Dialog (Console): "Phone Booth of the Future"
• Dialog (Trixie): "Kid Tannen"
• Interact with Console.
• Interact with Phone Button.
• Dialog (Console): "Phone Booth of the Future"
• Dialog (Trixie): "Some Guy"
The achievement will pop once you're back in control of Marty.
Credit to T_l_M_B_0 of PST