1. Build a scavenging station and assign assign a settler to it in every settlement. This gets you all resources(incl plastic).
2.Build brahmin troughs in every settlement. This provides a steady stream of steaming gold.
3. Link your settlements. Since settlers/provisioners are immortal and have inf ammo (cept for mini nuke/missile?) feel free to give them high speed miniguns and nuka grenades for maximum impact.
4. Build a bunch of general traders. This will give you a place to sell all that jet and allow faster fertilizer acquisition.
5. Profit. You now should be producing hundreds of doses of jet out of your sketchy post apocalypse meth lab. I usually get about 6k caps a day (in game) worth.
Always remember kids, time is a flat circle.