This is so easy, and you will save tons of money by making your own Bubble charms instead of buying them. More important, you will have only what you need, and nothing you don't.
First, gather your supplies:

• cardstock or thick paper
• a rubber stamp (lets say its a letter stamp, but any small stamp would be ok)
  
• pigment (or permanent) inkpad
• thin wire
• something round to wrap your wire around (a thick marker or film canister work well)
• clear glue (you want a nice thick glue like Aleene's or Diamond Gaze)
• wire cutter
• scissor
  

Here's how simple this is, step by step:

1. Stamp a letter onto your cardstock and let it dry
2. Wrap your wire around the marker or film canister into a spiral.
   
3. Slide your wire off the marker, and cut one 'loop' of wire.
4. Lay the loop over your letter, so your loop 'circles' your letter.
5. Pour glue inside the loop. You want to use a little extra glue. so it will dry 3D and look like an Acrylic charm. But you do not want the glue to leak over the wire loop.
6. Once it's dry (about two hours to be safe), cut out around the wire circle.

Congrats, you are on your way to designing your own 'Bubble Charms'