How did pixar create toy story?

Quick Answer
The provided evidence does not include details about how Pixar created the original Toy Story.
Explanation
The only verified information in the supplied sources concerns Toy Story 4, the fourth installment in the series. Toy Story 4 was produced by Pixar Animation Studios for Walt Disney Pictures, released in 2019, and directed by Josh Cooley. Its screenplay was written by Andrew Stanton and Stephany Folsom, with story and development contributions from John Lasseter, Rashida Jones, Will McCormack, Valerie LaPointe, and Martin Hynes. The film features the return of the original voice cast, including Tom Hanks, Tim Allen, Annie Potts, Don Rickles, Wallace Shawn, and John Ratzenberger, and introduces new actors such as Tony Hale, Keegan‑Michael Key, Jordan Peele, Christina Hendricks, Keanu Reeves, and Ally Maki. Set one year after Toy Story 3, the narrative follows Woody, Buzz, and the gang as they face new adventures and challenges.
No information in the provided evidence addresses the development, production, or creative process behind the original Toy Story released in 1995. Consequently, it is not possible to describe how Pixar created that film based solely on the supplied sources. For details on the original movie’s creation, additional reliable references would be required.
The information above summarizes what is confirmed: the existence of Toy Story 4, its production details, and its connection to the broader Toy Story franchise. It also clarifies the scope of the evidence and notes the absence of data concerning the original film’s creation.