Complex sentence: Jerry spots an umbrella salesman using the sales technique he invented, "The Twirl", but the salesman explains that it was in fact invented by Teddy Padillac, a longtime umbrella salesman Jerry once worked with.
Split into simpler sentences: Jerry spots an umbrella salesman using the sales technique he invented which was named "The Twirl". However, the salesman explains that it was in fact invented by Teddy Padillac, a long-time umbrella salesman who Jerry once worked with.