: Highlight your data range and press Ctrl + T (or Ctrl + L ) to convert it into a Structured Table . This automatically adds filters and alternating row colors, making the file much easier to read. 2. Data Entry & Validation
: Highlight your client name or email column, go to Conditional Formatting > Highlight Cells Rules > Duplicate Values . This will immediately flag if you accidentally add the same client twice. Kлиeнты.xls
: At a minimum, your client list should include the following headers in the first row: ID : A unique number for each client. : Highlight your data range and press Ctrl