For a simple yet charming home decor to celebrate a baby's 1/2 birthday and arrival, use pastel-colored balloons to create a soft and inviting atmosphere. Arrange flower-shaped balloons to add a playful and whimsical touch. Stick a "Happy 1/2 Birthday" wall banner to the wall to highlight the special milestone. This combination of elements will create a delightful and festive setup that is both elegant and understated, perfect for celebrating the baby's half-year mark and arrival.