When the American flag is to be flown at half-staff what is the procedure of raising and lowering the flag?

Should be first hoisted to the peak for an instant and then lowered to the half-staff position. The flag should be again raised to the peak before it is lowered for the day. By "half-staff" is meant lowering the flag to one-half the distance between the top and bottom of the staff. Crepe streamers may be affixed to spear heads or flagstaffs in a parade only by order of the President of the United States.