You don't want to go past the extended runway centre line when turning final. You could see those ahead of you while on Base and should be looking for traffic on final on your right before you lose sight of them when Banking., When turning left BASE before you turn, clear for traffic on your left. This requires looking back behind you. Way back we would press left pedal and apply aileron to the right to keep the wings level and fly straight This helps you see behind you. Some people Poo poo this but it works for light aircraft as long as you are at the right speed to do it safely. Nev