Whether you are an old hand at baking or new to the craft, these tips and suggestions will make all the difference in your success.

Assemble all the ingredients and tools needed before starting. Read the recipe through to get a sense of the processes and techniques involved. Using an oven thermometer, check your oven's temperature for accuracy.

Have a baking sheet at room temperature before placing dough on it; a warmer pan will melt the dough, causing cookies to run into one another. Run tepid water over the bottom of the baking sheet to cool it between batches of cookies.

Buy the best ingredients you can afford. The most important ingredient in most cookie recipes is butter. Use fresh, unsalted butter sticks for easy measure. Before you use it, bring butter to room temperature unless the recipe directs otherwise.

Eggs: Use fresh large white or brown eggs at room temperature. Cold eggs separate best, but after you separate them, bring them to room temperature so they will blend better with other ingredients.

Flour: We use unbleached all-purpose flour in most of our cookie recipes; unless the recipe specifies, do not substitute another kind.

Baking Soda and Baking Powder: Baking soda and powder are not interchangeable. However, you can substitute baking soda plus a little acid (usually cream of tartar) for baking powder.

Salt: Table salt is the default choice for baking; use kosher or other coarse salt only when specified.

Sugar: Most of our recipes call for granulated white sugar; use other kinds of sugar only when specified. Brown sugar is usually firmly packed into measuring cups for accurate measures. Sift confectioners' sugar before measuring, to remove lumps.

For greatest accuracy, use measuring cups, preferably metal, for dry and semisolid (peanut butter, jam, shortening, and such) ingredients. Scoop the ingredient into the cup and then level it with a straight-edge. Use the right size cup. (Never estimate portions.)

A liquid measure is essential for accuracy; place the cup on a work surface as you pour, and bend down to read so the marks are at eye level.

Use either parchment paper or nonstick baking mats to make removing cookies from the baking pan easy.

Most often made of heavy-duty wire, cooling racks allow air to circulate around cookies after they are removed from the oven.