Pull the customers Search Query Report in Google Analytics
Filter queries based on conditions including: Impressions, Clicks, CTR, Conversions, Cost-per-conversion, Bounce rate, Pages per session, Time on site.
For queries that don’t meet a threshold: add them as negative exact match keywords in the corresponding ad group in Google Adwords - and add a label to them. (For instance, this will be to add exact negatives to an ad group containing only phrase or broad match modified keywords)
For queries that do meet a threshold- add them as positive exact match keywords to the corresponding ad group (the one containing only the exact match keywords - and add labels to them. Or if no such ad group exists for exact match keywords, then create it – add keywords, and label them.