1. Exact and/or Phrase are always good, when monitored. Big ROI can be made on these specific keywords.
2. Broad match can eat up your budget, racking up lots of worthless clicks
3. Continuously adding negatives can really help cut worthless clicks for broad
4. Lowering CPC can help ROI, but you will lose a significant amount of traffic.
4.a. Focusing your creative can avoid some worthless clicks while keeping CPC reasonable
5. Keep a low daily budget in case of avalanches of traffic
Other opinions?
Dave.