1. Click Settings (while still in Edit Layout of Lead/Contact)

Figure: 77

2. Move the required fields from Avaliable Fields to Selected Fields

Figure: 78

3. Expand the Buttons Section by clicking on (+) at bottom right corner. Uncheck  New check box and move the Custom buttons from Avaliable Buttons section to Selected Buttons section as shown below.

Figure: 79

4. Click ok.