Butterbeer Glasses

I wanted to make these for a Harry Potter-thon my brother and I are going to have. Now I just have to make some butterbeer to go in these awesome cups. I got the glasses from Dollar Tree for a dollar (USD) each. I got the etching cream (Armor Etch) from hobby lobby for $8 USD. It looks like a small container, but I still have so much etching cream left.