Click the cell where you want the total to appear
Type =SUM(
Select the cells in the column you want to add
Type )
Press Enter
Use AutoSum by selecting the total cell and clicking AutoSum on the Home tab
Drag the fill handle down to copy the formula to other rows if needed
Use =A1+B1+B2 for adding specific cells in a column
Use =SUM(A:A) to add an entire column
Use =SUM(A1:A10) to add a range of cells in a column