- As each gift is opened, mentally assign it a value (perhaps a dollar value or a 1-to-5 ranking);
- When it’s your turn, average the value of all the opened gifts (whether or not they’re available for stealing);
- If there is a stealable gift “worth” at least as much as the average, steal it! Otherwise, open a gift. (Depending on the rules you’re playing by, not every gift might be available for stealing.)