Follow these four simple rules for success
1. Thaw Completely.
Partially thawed phyllo dough will crack when you try to unroll it. Resist the urge to thaw it quickly on a counter; the sheets will become gummy and stick together. Instead, thaw in the refrigerator overnight.
2. Prep Everything Else First.
As soon as you open the package, phyllo dough starts to dry out. And dry phyllo dough equals brittle, likely-to-crack phyllo dough. Measure out and prep all the other ingredients before you reach for the phyllo.
3. Cover While You Work.
To delay drying, work with just a couple of sheets of dough at a time. Cover the rest with a large piece of plastic wrap, then a slightly damp dish towel. (Make sure the towel touches the plastic, not the dough.)
4. Brush Strategically.
Most recipes call for phyllo sheets to be stacked and stuck together with melted butter. Use a soft pastry brush that won't tear the dough, and start brushing around the perimeter of each sheet before the middle. The edges are the first areas to dry and crack.