Inside the board

1. Select the board you wish to add the email into.
2. Drag an email from the left pane
3. Drop the email into the column/stage your email is in.

From default inbox view

1. Hover over the email you wish to add.
2. Click on the Freshinbox icon
3. Select the board you wish to add the email into
4. Select the stage where you want to place the email

Inside an email

If the email is not part of any board, you will see a dropdown to select the board

1. Expand the Freshinbox properties pane
2. Click on the dropdown to select the board
3. Select the board you wish to place the email into.
4. Select the stage where you want to place the email
5. Click on "Add to Board" button