Detailed instructions for working a group puzzle of type '50THBirthday'

This is a signature puzzle named '50THBirthday'

The 12 elements in each group of this type of puzzle are: 5, 0, T, H, B, i, r, t, h, d, a, and y.

Every group in the puzzle must contain exactly this set of elements.

Each row is a group numbered as shown in this 50THBirthday figure.

In a 50THBirthday puzzle, each row is a group numbered as shown in the figure above.

Each column is a group numbered as shown in this 50THBirthday figure.

In a 50THBirthday puzzle, each column is a group numbered as shown in the figure above.

Each 4x3 rectangle is a group numbered as shown in this 50THBirthday figure.

In a 50THBirthday puzzle, each 4x3 rectangle is a group numbered as shown in the figure above.