I've done a LOT of pirating on and off other plays trying to make it work. I've found out a few things...
* No-one is your friend, not even the one's who are ambivalent about your existence. Do not rely on them, but do *NOT* initiate hostilities with them either, you have more than enough enemies.
* Raiding around on system is rarely worth it, you are burning supplies trying to poach the small patrols or fleets while dodging the big ones. Move around, and get good at being PATIENT while looking for good opportunity targets.
* Talking big opportunity targets, low-defense colonies run by people who don't like you (most people) are usually soft enough for you to raid, often repeatedly, until you have filled your folds with goods. Get those to your nearest pirate base or otherwise 'friendly' non-pirate base as soon as you can, though you will have to smuggle your loot to their black markets to get any decent pay-out.
* Be picky with your ships. I've tried the 'horde of weak pirate ships' myself and it's the absolutely opposite of cost-efficient. These ships bloat your fleet, costs you more crew, fuel and supplies, and often are D-mod barely-floating wrecks you picked up somewhere. It's tempting, but unless it's a very cost effective hull (and you will find out what those are as you get more experience, or whatever conforms to your doctrine) break it for salvage and thanks pappa Khorne for the free supplies and materials.
* Hoard your weapons in whatever pirate base you name your home. Do NOT sell them unless you know for absolutely sure you don't want them, they generally are not worth much and will serve better being fitted to the replacements for the losses you will inevitably suffer.
* Be paranoid. There are a *LOT* of people out to get you - especially if you actually manage to be effective - and the WILL find you unless you are good at getting gone at the first sign of trouble.
* Be a prick. You are not looking for fair fights, you are looking to survive as the most hated individual in the sector - raid that planet when the chance presents itself, wipe out that small patrol and do salvage their best military hardware for yourself, DO extort money from that fleet out mining, or salvaging, or anything. Remember, money does not take cargo-space, and free money you don't have to fight for if effectively worth twice as much as it won't be used to pay for replacement assets.
* Finally, remember that sometimes hard work does pay off, and might even get a few choice people off your butt so you won't have to feel them breathing down your neck all day long. If a particular faction is giving you to much grief and you think you can take it, do go off and kill that bounty they want dead - so long as it's not another pirate, that would be a poor choice indeed. If you do enough dirty-work for them not only will they pay your your hard earned blood-money, not only will you be able to salvage the very ships that bothered them so much, but they will even improve standing with you, if only a little every time. Also, choosing to NOT raid their stuff - anymore - and making life hard for those OTHER folks who hate you and who happen to be hated by this faction, will help you too. ESPECIALLY if you manage to invade and TAKE one of their worlds, then gift it to that faction...
Finally, always remember - you are looking out for number 1 - by whatever means you can. The sector don't care about you and you don't care about them.
Now if only I was better at following my own advice