For Clothing:
Level 1 Clothing Item + Level 1 Clothing Item = Level 2 Clothing Item
also Level 1 Clothing Item + FASHION CORE = Level 2 Clothing Item
Level 2 Clothing Item + Level 2 Clothing Item + 1 x Good Luck Charm = Level 3 Clothing Item
Level 3 Clothing Item + Level 3 Clothing Item + 2 x Good Luck Charm = Level 4 Clothing Item
Level 4 Clothing Item + Level 4 Clothing Item + 4 x Good Luck Charm = Level 5 Clothing Item
Level 5 Clothing Item + Level 5 Clothing Item + 8 x Good Luck Charm = Level 6 Clothing Item
Wings Synthesis:
Wings Level 1 + 5 x FASHION CORE = Wings Level 2
Wings Level 2 + Wing Level 2 + (not 2) 5 x Good Luck Charm = Wings Level 3
Wings Level 3 + Wing Level 3 + (not 3) 10 x Good Luck Charm = Wings Level 4
Wings Level 4 + Wings Level 4 + (not 4) 20 x Good Luck Charms = Wings Level 5
(The increases from what I've been told is 5 good luck charms per level maybe someone with higher then level 5 wings can add to this so we have a better list)