Here are some ideas for putting logos and letters on round ice by using
an ice stamp.
Step1. Make a plat part on the ice by pushing a part of the round ice
against the flat part of the ice mold body.
Step2. Make the flat part of the ice face the ground side and put it in
a glass. It suppresses rolling of the round ice.
Step3. Press the ice stamp onto the top of the round ice in the glass.
Step4. Pour drink into the side of the glass so that drink does not hit
Now, when you drink, the logo will face the top and stabilize.
Please refer to the following video.