At the start of a match, each player must indicate how he or she will keep track of his or her life total. This method must be visible to both players during the match.
Commonly, players indicate their method by just using it at the start of the game – writing 20 20 on fresh sheet of paper is fine, setting two dice at 20 also is fine (though not recommended). A player’s “notes” need to be visible for both players, so if there will be any kind of discrepancy between each other’s notes, it could be noticed and fixed as soon as possible.
A shared method is acceptable as long as all players in the match have access to it.
That means someone can use one note pad (or smartphone on Regular Rules Enforcement Level) to track both players’ life totals. Of course then that notepad need to be available for both players.
A change in a player’s life total should be accompanied by a verbal announcement by that player of the new life total.
Players should always announce any changes in life totals verbally and their opponents should confirm each change. This way players reduce the chance of facing unpleasant situations by communicating the game state clearly.
If a player notices a discrepancy in a recorded or announced life total, he or she is expected to point it out as soon as the discrepancy is noticed.
If there is any kind of discrepancy in life totals, players are obligated to point it out as soon as possible so the players (and perhaps a judge) can find the source of that discrepancy and fix it. No one want to find out that they were one off from living through an attack because of a life discrepancy ten turns ago.