Piracy, the simple but deadly option.
Without any worries about pledging or political structures, lets take this back to the basics - Assuming you own a Sidewinder Mk II, you're going to need 3 things: hatch breaker limpets, cargo space, and some gun.
Take yourself to the lowest risk area of space you can find, this means finding systems in anarchy, either for political reasons or due to the fact that nobody lives there, now, get ready because you're gonna wanna find yourself a target, a low risk ship that has cargo ready for the taking.
Once you have a target, shoot a hatch breaker limpet at it, at this point, your target may try to flee or fight back, keep them busy, but dont kill them before the cargo is dropped, no, just wait til the time is right and go scoop that loot up, or use more limpets!
If you'd like to get away with this piracy game in non anarchy space however, I highly recommend bounty hunting instead, just steal cargo from your target first, and don't let any police catch you with any Trinkets of Hidden Fortune.