Three inches is the size that matches most of what inshore fish are eating — small pilchards, finger mullet, glass minnows and shrimp.
The paddle tail does the work. It thumps on a steady retrieve, putting out vibration that fish find on the lateral line well before they see the bait.
Olive is the natural choice. Over grass in clear water it reads as a real baitfish or a small pinfish, which is exactly what you want on a bright calm day when brighter colors get refused.