If you started with Iron Man tonight (I plan to) you could watch one movie a week until Age of Ultron.
After that you would have to watch two a week. I feel that Ultron is a good place to begin the two a week trend.
*Note there is a week gap between Black Panther and Infinity War because I will be at Star Wars Celebration
January 6th - Iron Man
January 13th - Incredible Hulk
January 20th - Iron Man 2
January 27th - Thor
February 3rd - Captain America: The First Avenger
February 10th - Avengers
February 17th - Iron Man 3
February 24th - Thor: The Dark World
March 3rd - Captain America: The Winter Soldier
March 10th - Guardians of the Galaxy
March 17th - Avengers: Age of Ultron
March 20th - Ant Man
March 24th - Captain America: Civil War
March 27th - Dr. Strange
March 31st - Guardians of the Galaxy: Vol. 2
April 3rd - Spider Man: Homecoming
April 7th - Thor: Ragnarok
April 10th - Black Panther
April 17th - Avengers: Infinity War
April 21st - Ant Man & the Wasp
April 24th - Captain Marvel (Go see it in theaters again!)
April 25th - Avengers: End Game