Speakers often get de-railed when they make a mistake. The way to handle that is :

A、Whenyoumakeamistake,admitit,andtrytonotdoitagain;
B、Apologizethreetimes;
C、Startallover;
D、Whenyoumakeamistake,MOVEON,theaudiencewon'tevenknowmostofthetime!