Step 1: Open the task wizard and select your task
Bring your cursor to the left of the task you want to re-sort. Placing it over the up/down arrow in the far left column will change your cursor into a hand icon. Click to grab the task you want to move.
Step 2: Drag and drop the task row into a new position
As you drag the row up or down, a red guideline indicates where that row will be positioned when you drop it. You can also quick-sort the entire task table by simply clicking on the Start Date, End Date or Title column headers.
Watch this quick video to see how it is done.