At the start of stage one, you will be on the far right side of the map above. A short walk to the right will take you past a beached ship. The crack in the hull (1) is actually the entrance to the first Labyrinth. For the time being, walk past the ship and continue right to reach the town. Take advantage of the easy to defeat Amols to earn experience and money (you'll need at least 130 metal), and to boost your health closer to 200.
The first house that you reach (A) will contain the town chief, who will personally advise you to gain experience and purchase weapons. The next house is locked. Walk through the forest and attack the Wasps and Poison Flowers as you encounter them. Once you make it through, Goblins will start to attack. They are strong and take a lot of hits to defeat, but they are easy to fight and will give you more experience points. Walk back and forth if you need to collect more money.
Beyond the field of Goblins, you will reach house (B) which contains an informant who tells you that each labyrinth has a treasure. When you reach the water, carefully jump from platform to platform and avoid falling in, which results in instant death. Avoid the Poison Flowers, but don't be afraid to land on one if it will prevent you from falling off.
Beyond these platforms, you'll arrive at house (C) which is a store that sells the Ring for 80 metal. Absolutely buy it since it will give your defense a much needed boost early in the game. She will also inform you that the Princess was abducted by pirates. Next door (D), you'll find another shop, and this one sells the Mace for 50 metal. You do not need to buy the Mace here, as it is not needed until Stage 2, but it is more powerful than your sword and makes a nice offensive boost. Purchase it if you can afford to. If you do, the shop keep will refer to the fortress inside the castle of the next stage.
The next house (E) offers you an opportunity to purchase vials of medicine, and the house after that (F) is an Inn where you can rest and obtain a password if you choose to stay the entire night. Continue to the right, and climb the steps to reach the bridge. Cross the bridge and climb back down, and you will encounter the creature known as Karukyunomu, a kind of hopping dragon. The dragon hops a short distance forward to the left, and then bounces back to the right. Stay ahead of it, and attack upwards at its head (with the Mace if you purchased it) until it is defeated. Then step inside the final house (G). Say "no" to his request to send you to the next stage, and say "yes" to his request to send you back to the shore.
If you have reached Class O and possess the Ring, you should be adequately prepared to enter the dungeon. Possession of the Mace is certainly helpful. Walk to the crack in the hull of the ship and push up to enter the labyrinth.
The labyrinth of Stage 1 is contained inside the ship. Compared to all of the other labyrinth, it is the simplest, but it still contains a number of confusing one-way passages and a circular passage. The enemies that you find in here are quite easy to defeat, but remember to keep your guard up, especially around the bouncing Little Dragons. The red line indicates how to reach the boss from the start of the dungeon while the blue line indicates the escape path.
From the start, climb down the ladder, and proceed to the right along the top level as far as you are able to. When you can go no further, climb up the ladder to the room above. This trip up is one-way. It does not matter if you take the upper or lower right door, but this trip is one way as well. Climb down the ladder, but do not go left or you will be moving in a circle. Instead, continue right, and you will actually wrap around to the left side of the boat. Here you will find a ladder that will permit you to climb down to the lower level.
After you climb down, proceed to the right. You will have no choice by to climb down again. Stay on the upper level and walk to the right. This trip is one way. Climb up the ladder that you arrive at. Continue to the right until you find another ladder that you can climb down. Fight the Devil Eyes and descend to the lower level. Climb down the ladder here to locate the boss of the labyrinth.
Despite the scary look of the labyrinth boss, Skulltas, you can actually defeat him quite quickly. Simply let him walk up to you, and stab upward at his head as he passes by. You'll take a little bit of damage, but if you stab quickly enough, he will be defeated with very little effort. Your reward will be the Magic Key, which is needed to access some of the future labyrinths.
To make your escape, you can take a much quicker route out of the boat. Climb back up two rooms, and proceed to the right along the lower level. Continue until you encounter the ladder that will allow you to climb up to the top level. Then walk one screen to the right and climb the next ladder to exit the labyrinth.
Proceed to Stage 2
At this point, you will have no choice but to walk all the way back to the right edge of town, and defeat the Karukyunomu again in order to access the old man in the last house (G), who can warp you ahead to the next stage (say "yes" to the first request.)