Sailing to the favored end of the finish line means you’ll sail a shorter distance.  If nothing has changed, and you started and are finishing on a beat, then the favored end will be the opposite end that was favored at the start.  Checking out flags and others boats may help you tell which end is favored.  Another method is to sail to the layline for one end of the line and tack.  Sail along the layline, and when you reach the layline for the other end of the line, see if one end looks closer to you.  If one end is closer, that end is favored.  Of course, by sailing to a layline, you risk overstanding the line.