1. Taking Accurate Measurements: This is the foundation of a well-fitting blouse. Carefully measure your bust, waist, hips, shoulder width, arm length, and blouse length. Refer to your pattern's instructions for specific measurements needed.

2. Pattern Selection and Adjustments: Choose a pattern that aligns with your measurements and desired style. Check for pattern ease (the extra fabric allowance for movement) and make any necessary adjustments to the pattern pieces to fit your measurements.

3. Fabric Preparation: Wash, iron, and then lay out your fabric flat. Pin the pattern pieces onto the fabric, carefully aligning the grainline (a line on the pattern that indicates the direction the fabric should run).

4. Cutting the Fabric: Using scissors or a rotary cutter, carefully cut along the pattern lines. Be precise! Cut the lining fabric pieces, too, if you're using one.

5. Sewing the Blouse Bodice: With right sides of the fabric together (the printed side facing inwards), sew the front and back bodice pieces together at the shoulder seams. Press the seams open.

6. Constructing the Armholes and Side Seams: Sew the side seams of the bodice, matching the notches (small triangles) on the pattern pieces. Press the seams open.

7. Sewing the Sleeves (If Applicable): Sew the sleeve pieces together, following the pattern instructions. Attach the sleeves to the bodice, matching the armhole curves.

8. Sewing the Neckline: Finish the neckline by folding the fabric edges inwards or by using bias tape.

9. Sewing the Back Closure: Attach your chosen closure (buttons, hooks eyes, or a zipper) to the back of the blouse.