I start with a chimney of hot coals and add one stick per 60-90 minutes after that. Air flow is the key. Also, when I add a stick, I keep the firebox door open for a few minutes to ensure adequate air flow to the new wood. Also, I put the wood on the firebox before adding to the firebox. This warms it up.
A small, hot fire will get you thin blue smoke every time
120 gallon reverse flow aka Hog Coffin, 18.5 WSM and starting SpatulaMan BBQ in 2013