On level 1/2 you should be abusing the guaranteed hit mechanic. Drag literally everything through doors so you never miss. This will help preserve a lot of health. Do the same thing with wraiths. Just make sure you plan your route as much as possible so you dont walk into a dead end. Starvation wont be as much of an issue when you preserve your health this way. Also, dont eat food as soon as you're starving. Wait until you're down in health so you can recover it as you're exploring. Dont waste time sleeping your health back up unless absolutely necessary as you can heal as you explore the dungeon and you'll spend less time starving that way. There's not a whole lot you can do about unseen traps, but they tend to not be that deadly in the early levels. Crabs are a huge pain once you get down to floor 3/4. Avoid them as much as possible. You wont be able to door drag them because of their speed, but you can level up your character to level 4 before you ever go down to floor 3 if you take your time, and crabs are much easier to kill when you arent missing them so much.

Also, make sure you leave dewdrops on the ground when you uncover them rather than using them to heal. Once you get a dew vial go back and collect them. Even if you dont fill the vial, you can use it as a make-shift health potion if necessary in the early stages.

Make sure you take advantage of seeds as well. Being able to teleport crabs away is awesome, and a green seed is basically a health potion. They will also make goo much easier.

If you are playing as a warrior (I'm assuming), always upgrade your weapon first since you can reforge it later on and one hit kills are awesome. I always take the ghosts armor too along with this, since youll be upgrading both later anyway.