I start by getting the first slave from joining a guild and buying another slave. I send one of them to the location with the magic logs to recruit Lilia while the better fighter and I go to an easy dungeon. I then do whatever I can to make money until day 3 when you can get Daisy from Aliron streets for 200 (or 100) gold. I now have 5 people in the house and can collect 50 wood and 25 cloth to upgrade to 10 rooms. Buying wood, stone and food is faster than harvesting at the moment. Buy any tools you can so you can collect faster, 15-25% for <200g will pay for itself in just a few days.
Other tips:
Use dates to improve physical for anyone so they can collect faster and do more damage in combat.
If you can buy any tool that is 45% or more get them as soon as you can.
Get an Attendant, collect cloth and make bandages to heal your fighting parties cheaper.
Equip everyone with the best weapon they can use.
Buy all shards you can.
Upgrade Forge and Tailor as soon as you can.
Send your strongest characters to collect mythril and sell it for 75.
Once you can collect 10+ mythril per turn, save up and start making mythril picks. Later make all tools out of mythril.
Upgrade the guild quests to tier 2 as soon as you can. Do not upgrade quests to tier 3.
Upgrade the workers guild with disassemble as soon as you get 100 points.
When you need obsidian buy and disassemble items until you can mine it.
Never buy usable items from guilds.
Don't bother upgrading guild hirelings.
Always send a thief and a healer with the party to dungeons.
Archers are the best class to start with, upgrade them to snipers as soon as you can. Don't bother with knights or paladins until much later.
Bandit forts have ballista that are immune to air but weak to fire, use Snipers and Scholars
Rogues and casters are best in jungles, giant ants are weak to water and immune to air and centipedes are easily stunned by lightning.
Harlot+Succubus will gain xp a lot faster by draining other's lust.
Cooking is an easy way to make money early in the game.