“Be extravagant. As much as you might mean it, don’t end with “Sincerely,” “Cordially,” “Affectionately,” “All best wishes” or “Yours truly.” Their punctilious formality smacks of someone who wears wing tips to bed. If you’ve done your job up till the last sentence of so intimate a letter, the swooning reader won’t notice the omission of this epistolary convention. Be bold. Skip it.”