Migrating and adding tempdb files

Hi,

I'm in the process of migrating tempdb to a new, dedicated drive. In current state, the SQL Server instance has one tempdb data file. Per best practices, I would like to add three (3) additional tempdb data files while also migrating to the new drive.

My questions are:

• If the allocated space is 100 GB and I wanted to add 4 tempdb files to that drive, should they all be of equal size (25 GB max)?
• Do I add the tempdb files first (of 25 GB each) to the new drive and then migrate the existing tempdb file? Or, should it be reverse (first migrate then add)?

I'm fairly new to SQL Server maintenance and improvements and any and all help is appreciated!

David