Use the R key while the transport is in motion.
You can record a little early and stop it a little late, then Slip editing the ends.
What your looking for when trying to make a clean splice is the zero crossings point.
zero-crossing is a point where the sign of a mathematical function changes (e.g. from positive to negative), represented by a crossing of the axis (zero value) in the graph of the function. It is a commonly used term in electronics, mathematics, sound, and image processing.