Part 1
Add the following to Rule 2.7 entitled “Dealing and Play”:

There will be a GNDT entry entitled “TBTH” for each player.  This column will track each player’s Total Bet This Hand.  Every time a player calls or raises, the amount of their call or raise is added to the TBTH column.  At the end of each hand, all player’s TBTH columns are reset back to 0.  For example, if a player bets $50, and then later in the hand raises $25, their TBTH would be $75.

Helpful for keeping track of who is eligible to win what, especially in terms of all-ins and side bets.

Part 2
Add a Rule to the Ruleset entitled “All In” with the following text:

If at any time a player bets all of his money on a single hand he is considered all in. Once having gone all in, a player may not make any more bets during that hand.  Any bet which would be considered a raise to the all-in bet would then be distributed into a Side Pot, in such a way so that the portion of the raise that calls the all-in bet is placed in the main pot (i.e. “ThePot”), and the remainder of the raise then placed into a separate GNDT row entry entitled “SidePotX”, where X is the number of the Side Pot (in cases where more than one side pot exists).  If there is a bet of all-in after an initial bet of all-in has been placed, another entry in the GNDT is created entitled “SidePot(X+1)” where X is the number of the previous SidePot GNDT entry.

If a player makes a bet of all-in that is not high enough to call any previous total bet (including another all-in bet), another side pot is created in accordance with the rules for creating side pots above.  The main pot will then be adjusted to reflect the maximum winnable by the player still invested in any pot with the smallest total bet, and any remaining balance will then be distributed into the remaining side pots in such a manner that each side pot, if added to the main pot, then reflects the total winnable by the player with the smallest total bet still invested in that side pot.

The players who are invested in the side pot with the fewest invested players determine the winner of that pot in accordance with the rules for determining winners of hands.  The winner of that pot then becomes invested in the side pot with the next fewest invested players (or the main pot if there are no other side pots), and winners for each side/main pot are determined as usual.  A player who makes an all-in bet is not eligible to win any of the money in a side pot they are not invested in.  A non-seated player may not be invested in any pot.