Click on the add-label icon in any fretboard's toolbar and a new label will appear below the fretboard. If not already there, a resizable container will appear as well.
You can click and edit the text contained in the label.
When you move your mouse over a label three small icons will appear, click on the 'C' icon and then click on a color in the pallette panel, the label will change color.
When you move your mouse over a label three small icons will appear, you can click and drag the label from the first small red icon.
When you move your mouse over a label three small icons will appear, click on the 'X' to remove a label.
This is the area where labels can be positioned, it will appear when you add at least one label and disappear when you delete all labels. When you move your mouse in this area it will be highlighted in yellow and a grey arrow at the bottom will be visible, you can use this arrow to resize the labels container and allow more space for positioning your labels.