Excel tricks learned this week

Customize the "Quick Access Toolbar" on top left, then you can command+shift+number of the command(from left to right, starts with 1) to use that command

option + click the sheet name to copy the sheet

When there's empty cell in a column and you want to sort it, a window will pop up and you select "expand to all" to correct sort (the empty cells will end up at the bottom)