When making all types of edible bubbles, make them within a day or two of cake delivery as they will slowly start to shrink in size as time goes on. And make sure you make a lot so you have enough to cover your project with them accordingly!
Store them in an airtight container in the fridge if making in advance. Agar agar pearls can technically last for up to 7 days refrigerated.
To make the agar-agar bubbles...

Pour oil into tall, glass container and put into fridge until reaches 32 degrees F
Mix 6 grams of agar-agar into 1 and 1/2 cups water. Whisk over high heat until boiling and then remove from heat.
Let cool slightly, and start dropping into cold oil.
Strain out oil and rinse bubbles with slightly warm water to clean!

To make the liquid-filled bubbles...

Mix 1 gram of Sodium Alignate into 1 cup of flavored water (or other drink) and blend with a hand mixer until fully incorporated.
Mix 5 grams of Calcium Lactate into 4 cups of water and stir.
Drop the SA mixture into the CL mixture gently and stir for 3 minutes.
Capture bubbles from the CL mixture with a slotted spoon and place in bowl of water to stop the process.
Strain out bubbles!

To make the gelatin foam...

Pour 20 grams of gelatin into 200 grams of seltzer water and mix well.
Put in fridge for 10 minutes.
Take out of fridge and heat on high on stove, stirring until just boiling and then remove from heat.
Let cool slightly and use a hand mixer to create bubbles.
Put in fridge to set.