1. Start with the easiest clue anchors
In Fullmetal Alchemist mode the series clue is already spent, so your first job is to separate 6 characters, all listed for 2003. Gender is a blunt tool here (4 are male and 2 female), and none hair appears on only 1 of them, while blonde covers 3.
2. Use contrast instead of repetition
Start from Alphonse Elric, then change axis instead of staying inside the same visual group: yellow eyes are the rarest tag at 1, and black the most common at 1. Two guesses that share a hair colour burn a slot without narrowing anything.
3. Review the pool after each game
The overlap worth memorising is this: Riza Hawkeye and Winry Rockbell agree on 4 of the five clue traits. In a pool of 6, that single pair decides most failed runs, so learn how the two differ before the next daily puzzle.