Your first captain is going to die. I don't mean this is in a "you will fail" sort of way. I mean this in a "if you intentionally kill yourself, you can get a leg up" sort of way. The goal here is to basically get yourself a bunch of free echoes (in-game money) right off the bat with minimal amount of effort. There are a variety of reasons for this, but the biggest one is that gathering money at the start of the game is fairly tedious, and you have to invest in a few starting pieces of equipment early on to do a number of useful things.

The trick, then, is to get over this hump ASAP.

There are some income sources which are limited on a per-game basis, and in any case, you'd have to play for hours and hours to get lots of money.

The trick, then, is to cheat as much of this out of the way as possible to minimize the amount of time (and frustration) spent trying to gather echoes, the in-game currency.

The core "roguelite" mechanic of this game is the legacy. When a character dies, wins, or retires, he may pass something on to his/her heirs.

There are five legacies: Pupil, Salvager, Shipmate, Correspondant, and Rival. There is an achievement for picking each one of these, so if you want to get them all, it might be worth killing yourself on purpose at the start of the game repeatedly to quickly acquire them all. The simplest way of doing this is to sell your initial ship for the only ship you can buy and then leave port (press E) and crash immediately into an adjacent wall. Rinse and repeat for each legacy, if you want those achievements the easy way.

Once you're done with that, what you want to do is pick an initial background which gives you 20 echos to start out with. Go to the shop and sell off all your fuel and supplies. A message will pop up that some shady character wants to meet with you. Pick up his "dispensation". Sell it off as well. Sell your gun. Now, you want to go to the shipyard and trade your ship in for the cheapest ship - the one that gives you 500 money for it (it registers as a trade for -500). You'll have about 600 echos at this point.

Now drive into the nearest wall to sink your ship.

Yay, you're dead!

Pick the legacy "Salvager" - this will pass on 50% of your veils to your next character.

Now, repeat the above process twice more. The second time, you'll end up with about 900 echoes, leaving you with 450; the third time, you'll end up with 1000, leaving you with 500 in your next life.

Okay, now that you've cheated up to 500 echoes, what next?

Pick the urchin background.

You're given the mission at the very start of the game in London to drag a Tomb-Colonist off to Vanderbight, which is to the north of London along the coast (not a spoiler - the game tells you this when you get the mission). Don't turn her into the authorities when you get to Vanderbight, and she'll give you 250 of the game's currency - echoes. At this point, you'll want to do this - just sail along the coast north to Vanderbight, drop off the colonist, then sail back to London. You should have 750 echos at this point.

What you want to do now is sell all your stuff and sell your ship, buy a townhouse and write an ironclad will. The ironclad will ensures that this house gets passed on to your next character. Now you are, effectively, 1000 richer when you start your game out.

At this point, you have the option of doing some more cheating. And you should.

Repeat the money-making process once, making sure to buy an ironclad will this time around.

However, after this, on your next character, you're going to want to, after you do all your stuff to make money and buy another ironclad will, go into the gun shop and purchase the 500 echo deck gun.

This time when you die, choose the rival legacy.

Voila! Now you've got a townhouse and a 500 echo gun to start out the game.

Feel free to play the game as normal from here; you've given your first character the equivalent of 1500 echos, saving yourself a fair bit of grinding for money, as well as giving yourself the ability to buy an Ironclad Will very early in the game.

MINOR SPOILER

If you choose A Shadowy Past, it becomes possible to complete a fairly early-game quest (the Sphinxstone quest taken from the Salt Lions) to get a very strong attribute-boosting item which is persistent across future characters. This is the only way to get this item (it will give you +25 veils), but if you choose another background, don't worry about it too much.