Recording live will force you to make choices during the recording process (mic selection/placement, phase, relative levels of summed signals and others). To make the most of the experience, document those choices. Write down what mic was used on what, where it was placed, what pre-amp it was plugged into, the phase and gain setting of the mic, etc. all the way to the signal VU peak for each track. This will force you to a) realize that you are making a choice and b) create a reference that you can go back and learn from.

A clipboard, a good piece of paper and a good pen (and a filing system) are very under-rated studio tools.

Good luck,

= Justin