Personally I'd recommend doing commerce as a means of making money. You gain gold, ducats (for commerce outpost store only) and exp for leveling up.

It starts off slow but as you obtain more ducats, the growth becomes exponential.




Preparation:

Complete the "Horrifying Herbert" Quest which can be started by equipping any type of Knuckle (besides your bare knuckles).

Purchase a Handcart from the Ogre Transport Helper with the rewarded Ducats.

Have a decent rank Windmill or Crash Shot for dealing with Bandits.





Recommended Trade Routes:

Less than 100,000 Ducats - Bangor to Port Cobh (Ruiha's Route)


Less than 100,000 Ducats - Port Cobh to Tailteann (Kouta's Route)


More than 100,000 Ducats - Tara to Emain Macha (Ruiha's Route)





Bandits:
As boring as it may be, pay attention to the road especially at higher trade yields.
Use WSAD keys to move instead of mouse as it will give you the best leverage to avoid bandit nests and keeps you from not paying attention.
When carrying a large yield, travel in a group if possible.

Caution:
If you are traveling in a group and you are ambushed, keep your transport as close to the ambushed player's transport as possible. This makes it easy to keep bandits from stealing your stuff by use of Windmill.

Reason being that if you place your transport too far, you will not know if bandits are robbing your transport. There is also a chance that another bandit nest could spawn on top of your transport.

Profit:
Try not to be tempted into spending your Ducats, save it for after you obtain better transportation.