Complex sentence: In 2002 he started working with fasion designer Karin Jimfelt-Ghatan on his design ideas, and together they started the internationally successful clothing company Odd Molly.
Split into simpler sentences: In 2002 he started working with fashion designer Karin Jimfelt-Ghatan, and along with her started working on his design ideas. Together they started the international successful clothing company Odd Molly.