Just drag and drop. Click and hold on anywhere in the row of the contact you'd like to move, drag it up or down, and drop it where you'd like.
Note: For security reasons, you cannot drag and drop contacts from one organization to a different organization. If you can't seem to drag and drop at all, it is because you have not been given the appropriate permission by the administrator of your list. Check with him or her, or contact us (firstname.lastname@example.org) if the problem persists.
Keywords / tags: order, re-order, reorder, arrange, re-arrange, rearrange, edit, drag, drop