Suppose you hit your tee shot OB and then pick up.  Say it’s a par-4 and you’d like to record a score of 6. Enter 6 shots, e.g., tee shot, double penalty, re-tee shot, iron shot, putt, putt.   On shot 3, “re-tee shot,” press in the SG column to turn shots 3-6 into “pickups.”  Your shot 1 tee shot and penalty will be recorded as “real shots” for SG purposes, the pickup shots will be ignored for SG results (since they didn’t happen) and your score for the hole will be recorded as 6 (so it’s easy to understand your final round score).