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

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

3. Expand the Buttons Section by clicking on (+) at bottom right corner. Uncheck New check box shown below.

4. Click OK

5. Save Contact/Lead layout

Next Step

Using Sitecore Analytics in Salesforce (Version 3.x)

or

Using Sitecore Analytics in Salesforce Lightning (Version 3.x)

Steps