What is the most efficient way to split up raw video into rough clips using Premiere Pro?
You're probably better off making subclips.

Subclips are pieces of footage that have been pre-edited, and appear in the project window as a separate clip, although they reference the same footage. In newer editions of PP there is the option of creating hard and soft subclips.

NB you can use the keyboard shortcuts i and o for setting in and out points and ctrlu for making the subclip (instead of noobishly clicking with the mouse like the guy in the tutorial). That will save your carpal tunnel.