Without a GPS (and to double check your GPS settings), rely on line sights. Start at the weather end, on starboard tack, closehauled, loosely trimmed and moving slowly, four to five boatlengths below the line. Start taking line sights with something onshore through the leeward end of the line. Ideally, you’ll have one at four to five lengths, three lengths and two lengths off the line, as well as the final shot right down line. Those early “safe” line sights are crucial in gauging the speed and timing to the line, because invariably the sights down the actual line become tough to maintain in the last 10 seconds, when the fleet is lined up. Sometimes a line sight to weather through the committee boat by the forward crew can be a valuable check in the last 10 to 15 seconds.