A left hand slap is achieved by literally slapping the string onto the neck with the left hand. This produces a percussive effect similar to a ghost note. Left hand slaps most often occur on the 4th string, but can occur on other strings as well. A left hand slap is indicated by the letters LS above the tab. As with any new technique, practice it slowly at first and listen carefully to make sure your notes are clear and even.
Example 368 uses the left hand slap on the E string. Practice first alternating between T (right), LS (left).
Example 369 incorporate the left hand slap and cross-hammers.