I ordered my air plants from Amazon. I use a spray bottle and spray them twice a week. To make the holders I used: two sizes of twine, embroidery hoops and a hot glue gun.
To make the balls, I just used different sizes of embroidery hoops, based on what size ball I wanted. Once I connected them together, I tied them with twine by criss crossing the twine to hold them in place so the hoops wouldn't move.
I then decided to add a thicker twine to make it look more visually appealing and give the plants a place to rest. I started in the middle and just kept spiraling around. I used hot glue to keep it together. A clip was placed while the last piece dried.
The larger one worked better if I did the larger twine on the inside of the sphere. With the smaller hoops, I adhered the larger twine to the outside. As you can see I attached the smaller twine to the top so that it could hang. It was tied on before I started spiraling the larger twine.
I then used another embroidery hoop and the smaller twine to make a mobile.
For these I simply used a smaller twine and wrapped it around tightly in a spider web pattern and then used the outside hoop to hold it together. I screwed the embroidery pins tightly so they would stay together. No hot glue was needed for these.