Hereafter, you can find some general advice about techniques for learning touch typing.
To be efficient when learning touch typing it is important not to simply try to type as fast as possible but to keep a steady speed and find a natural rhythm to press the keys.
The next important thing is to focus one's attention on accuracy. Only if you mastered the use of the currently unlocked keys, which means you make only very few errors with them still, you will have chance in the following lessons with even more keys to handle. You will notice you become almost automatically master if you make only very little errors and you will save precious time if you don't have to correct that many errors.
That is also the reason why the default accuracy level to unlock the next lesson is at 98% while the speed requirements are pretty moderate with just 180 characters per minute.
If you made mistakes it's important to correct them efficiently. Correcting single characters is almost always slower than correcting the whole word. For the latter you have just to press Ctrl+Backspace, and retype the word. The mental overhead for this is very small. For the first you have to first locate the your mistake, delete precisely to the location of the error, determine the missing part of the word re-type it. This requires way more concentration when retyping the whole word.
If you open any dialog or switch to different application while you are in a training session the training is paused and the timer is stopped until you focus Typewriting Trainer window again and hit any key.
The training session will also be paused if there will be no activity by the user for five seconds.