Short answers, pulled from the story.
Makoto first appeared in Street Fighter III: 3rd Strike in 1999. She was originally conceived during development of Street Fighter III: 2nd Impact but was moved to 3rd Strike after the team ran out of time to implement her properly.
Makoto was designed by Keigo Chimoto. Developer Hidetoshi Ishizawa was also closely involved and praised by Chimoto for his ability to adapt when the character was moved from 2nd Impact to 3rd Strike.
Makoto uses Rindo-kan karate, her family's dojo style, and is classified as a rushdown character. Her gameplay focuses on closing distance quickly and delivering powerful strikes, built around the karate concept of ikken hissatsu, which the development team described as "simple, direct and powerful".
Makoto was the most popular character in location tests for Street Fighter III: 3rd Strike in both North America and Japan. In Capcom's 2018 worldwide poll she finished second among all Street Fighter characters.
Makoto's loose, oversized gi belonged to her deceased father. The garment was an intentional storytelling choice by the development team to reflect her mission to restore glory to her father's fallen dojo.
The yellow ribbon around Makoto's neck was added by the Street Fighter III: 3rd Strike development team to communicate her speed and trajectory during a fight and to telegraph specific moves to her opponent. When she appeared in Super Street Fighter IV, the team had to write entirely new code to replicate the ribbon's flutter effect.