Forgetting when delivering a bayaan

Q: I listen to Islamic lectures, 6 points and talks all the time and I always forget what they say almost instantly but afterwards if someone talks about a section from it I am able to easily recall it most of the time. But sometimes when I am in Jamat/Tableegh/Path of Allah, and I become appointed to give a bayaan/ talk on 6 points or something I can barely recall or access anything in my memory even though I have so much knowledge about it somewhere in my memory. What should I do?

Sunnah method of using a miswaak

Q: I would like to know the masnoon way of doing miswaak. Should it be right to left in one go which would be the "length" of the mouth and the "breadth" of the teeth or is it to be done in an up down motion on each tooth starting with the tooth on top on the right which would then be the "length" of the teeth and the "breadth" of the mouth?

Touching an impure object

Q: If there is impurities on an object and I touch it with wet hands. I'm not sure if there was physical signs of it coming onto my hand and I touch a cloth with the same wet hands but you can't see the impurities on this cloth. Did the cloth get impure? If at a later stage my hands are clean and wet and I touch this same cloth but there are no traces/signs of the impurities on my hand, is my hand impure?