Tips

Kill ships
Killing SOC ships is a great way to acquire materials for your own ship or just get some good cash. Using the dismantle tool (orange wrench) you can either get a bunch of blocks or you can just harvest the equipment, such as propellers, engines, balloons, and is the only known source of driftstone items.

Mining for Money
Wood blocks are good money makers early on. A tree comes with lots of them, takes a single hit with the starting mining tool to knock down, and almost always have healing nuts or tree sap (for rubber). Stone blocks sell for $1, but so do stone background blocks (1 stone = 20 blocks). So you can take a little time and get 20x the money for those. Dirt is good for gunpowder, but sulfur will limit you early on, otherwise, it's good thing to drop, if you don't carry around an item stash. Once you have a little iron and can make an item stash, you can just strip mine areas for profit. High strength and blade will let you mass mine. High wisdom and a whale will too.

An other way is to build a mining ship with steel grinders. Use a baseship with enough buoyancy. Place a long row of blocks verticaly on the right side of the top of your ship. For the beginning use 10 or more steel grinder placed on the left side of the blocks. Move the ship from right to left below an island and grind the island slowly away. Collect the loot that is falling down on top of your ship. Good placement of the grinders prevent dirt and sand trickle on your ship. The grinder part of the ship can be realy big and grind down whole islands in no time. 70 or more steel grinders are possible.

Feels like cheating
MoneyMachine details an exploit-like easy way to make tons of money.

Equipment
Waiting until 100 wisdom to make your own ship gear makes sense. Supply your ship with the best of the looted goods from your enemies. Buy heavy machine gun ammo every time you hit town, your ship will chew threw a ton of it. You can make your own gunpowder in quantity once you have a gas mask to get into the poison layer and get the masses of sulfur.

Kraken
Killing Kraken is much harder than whales. They start out hostile and they can chew up your ship far faster. For some play styles, it's almost better to get out of the ship and shoot at it with hand weapons. Shoot for the face, the shell bits take almost no damage. Vulcan (fire status) weapons are your friend. You can tame them, but staying on top of them is much hard.

Buoyancy
You can use balloons but they are really not safe to have outside your ship. You can solve this by placing several smaller balloons inside an armored box. Place this box below your other equipment so that if the do get blown up, the fire balls don't burn their way through your whole ship.

Mining
Mining with a good knife is much faster as with a jackhammer. High strength on 100 improve the mining range with a knive even more. Jackhammers are only usefull for precise mining or for very hard materials like kraken shell or adamant.