The 'How To Lose A Guy In 10 Days' actor proposed to the Brazilian model last Christmas Day and he wanted to make it as exciting as possible, so decided to hide the ring in lots of parcels.
He said: "It was the last gift to be opened and I wrapped it in seven different boxes so Camila would have to keep unwrapping."
Matthew - who has two children, Levi, three, and two-year-old Vida, with Camila - says once the brunette beauty found the ring, he got down on one knee and popped the question.
He told People: "She got the ring, I took a knee and asked her to marry me and take my name. After a bit, she conceded ... thankfully."
The couple - who have been in a relationship for five years - married at their Texas home on June 9 and the couple are excited about what the future holds.
Matthew said: "We decided to embrace the ritual of marriage as an opportunity and adventure we'll take together."