If you fly in inhabited systems, scan all the ships that you can, and also get a wake scanner to scan some wakes as you travel. That would be a good start on collecting encoded mats. Once you start combat get a k-warrant scanner to increase payout. You can always go to a high res and help the system security ships. Once the target has gotten the shields and 50% hull stripped get into the fun. They won't shoot back at you as you've done much less damage than the other ships. A good way to get started, and also bring some limpets and a collection limpet controller, then hover up the manufactured materials as they drop. For raw mats you can collect some by mining or shooting/collecting stuff with the SRV, but best are probably brain trees and the crystal shards.