Step 1 Design you template label same way you design classic label. You can place initial pictures and texts, choose colors etc.
Step 2 Choose File/Save As…, change File Type to CD Label Designer Template Files (*.clt) and choose name.
After this, your label template is ready and you can use it for File/New From Template and File/New Label Wizard options.
Note: When you choose plain File/New option, template from Default.clt file is used automatically. Thus, if you want to change default template you need to edit this file.
See also:
How to use earlier prepared template?