My process is to:
1. Check the table of contents for potential candidates.
2. Check for headings and sub-headings.
3. Frequent the index for heavily referenced words.
Don't let this step get you stressed. The trigger words serve as cues and as curiosity prompters. Although it's best to get them in the beginning, if you don't find much, consider looking for triggers words sometime after PRing. Then your mind will be in a good position to help you out.
