I suppose you know the idea of any sorting method, it does a comparation and then swaps if they are missplaced. In what order and which ones depends on the sorting method.

When you compare two strings you use > or < operator, you can do the same for integers, but for dates you need use datediff function, and check if the result is smaller than 0.
If Datediff("d",Date1,Date2)<0 then 'do the swap.

you could replace the "d" with a "s" if you work with datetimes.