Data Modeling in Sql Server

I have to create a new database for a new set up and design the tables for future use.
The data is to be imported from excel sheet . The data contains the daily reports from the operations team . Which are the key points that needs to be looked into while designing the table and importing the data. I have listed down few points.
They are

  1. Check whether there are unique fields in the data
  2. Decide on primary and foreign keys
  3. Design the tables as per normalization

Can anyone add more points to it. I'm doing such a project for the first time. Thanks!!