Use a standard measuring spoon labeled 1 teaspoon
Fill the spoon to the rim
Level off the top with a straight edge
Do not pack the ingredient unless the recipe says to
For liquids, fill the spoon carefully to the edge without spilling
If you do not have a teaspoon, use 1/3 tablespoon
For dry ingredients, spoon the ingredient into the measuring spoon, then level it
For sticky ingredients, lightly coat the spoon with oil or use a second spoon to transfer it