Blocking is an essential technique for shaping and sizing a hat. It allows the fibers to relax and stretch into place, ensuring that the hat fits as intended. Moreover, blocking can help smooth out uneven stitches and tension discrepancies, resulting in a more professional and polished appearance. Soak the knitted hat into lukewarm water for about 30 minutes or until it absorbs enough water. Roll the wet hat gently in a towel to remove excess water. Lay it flat on a surface to dry, shaping it to your desired size. Let it dry completely in a ventilated area, away from heat or sunlight.