You can rearrange Tasks by dragging and dropping them in the position you’d like them to be.
Click on a Task (recommendation: from the right end of it) and then drop it where you’d like it to be. You should see a line that indicates where the item will be dropped.
You can also indent items (creating subtasks) by dragging the item inwards.
You can drag a Task along with any of its sub-tasks in one step by holding down the control (PC) or command (Mac) key when you click on the top Task before you drag.