What do you need a guide for? If you walk into a level it tells you what number it is. If you arent supposed to be there yet, leave. Otherwise, you just walk around to find the levels. The map is actually tiny compared to modern games.
Everyone has to have a taint. It's anatomically required. ~Vork - "The Guild"
Do what I did when I was 8. Get the blue candle. Burn a bush. Leave the room and come back. Burn the next bush. Leave and come back. Do this until you find a staircase. Do this in every room in the game. When you're finished doing that, bomb every wall. Also, in the second quest, make sure to blow the whistle in every room too.
There can only be only one staircase/case in a room so if you find one you can stop, there won't be another. See? So easy!
At least it's not the first Dragon Warrior. That was aimless wandering on an enormous map, or aimless wandering in enormous dark rooms where you can only see tiny a 3x3 square around you at any given time.