How can we auto populate Date, Time In and Time Out in a spreadsheet?

We are trying to build an excel spreadsheet to monitor people coming and going from an art studio in an Retirement Community.  

I feel there should be a way we can automate and populate the date, time in and time out without telling our membership to use ctrl + ; or ctrl + shift + ;.  I was just hopeful for one keystroke to fill the data in - from the system date.