Measure the amount of substitute flour using the same flour quantity your recipe specifies (use the table’s 1:1 guidance where listed).
If your substitute is DIY-based (flour + leavening), measure baking powder/baking soda precisely and add salt only if your recipe doesn’t already include it.
Mix the dry ingredients thoroughly before adding wet ingredients so the leavening distributes evenly.
Expect faster lift than plain flour: once mixed, proceed promptly to the oven to preserve carbonation/leavening strength.
If your bake turns out flat, increase leavening slightly next time (small increments) and verify your baking powder is fresh.