To change formatting of a tree labels select the Labels Formatting toolbar button or the Tree settings Options Panel tab:

<center>
     <br>
     <img src="/wiki/download/attachments/4227581/Changing Labels Formatting.png"/>
     <br>
</center>

Here you can select color, font, size and attributes (bold, italic, etc.) of the labels.

Note that when a clade has been selected the labels formatting settings are applied to the clade only.