1. A clean glass vessel. I recommend one large enough to get your hand in, it just makes it a little easier.
2. Plants. Any kind of plants you want they just all have to have the same living/growing requirements.
3. Charcoal, you can find this at any nursery.
4. Rocks, any kind you want. Pretty rocks, or just regular rocks.
5. Sterile Potting Soil, meaning not just from the yard, you dont want bugs or roots, get a fresh bag.
6. Chop Sticks, Trust me you will need them.
Go on an adventure to find all of your items
Clean your vessel with hot soapy water, no cleaner. You dont't want chemical reside killing your plants
Fill the bottom inch or so with rocks for drainage.
Add a layer of charcoal on top of the rocks about 1/2 inch give or take. This is for more drainage.
Add your soil on top of the charcoal, as much as you want depending on the look you are going for.
Ready your plants for their new home. Carefully break up the roots and get rid of most of the soil around plant.
Arrange your plants in their new home. A terrarium should have a front and a back so place accordingly. You can use your chopsticks to place plants, stones or decorations you want in your new terrarium. Try not to touch or get the inside glass dirty, it gets a little hard to clean it off in the end once all your plants are in your vessel.
Find a place to put your terrarium and enjoy!
Water a small amount every couple of weeks. You will know if you have watered too much cause condensation will build up inside, remove top and let dry out a bit and you should be fine. I love the way it looks in front of the window with the light coming through!