As submitted by member jakeslashgod, here are some fun things you can do on Katamarius, the online lobby you're at before entering a game.

• if you go up to the teddy bear holding balloons and press A your cousin walks around with a balloon
  
• if you go to the white circle with colours round it and walk into the circle your cousin will leave a trail of the colour you passed through
  
• if you push one of the large balls into the hole to the left of the stage there will be a clapping sound effect and the ball will reappeer at the top of the stage
  
• if you push one of the balls between the rainbow goal posts on either side of the stage the flower near the goal post will register it as a goal and the 0 will turn into a 1 on the flower

Any missing? Send them to vix and she'll add them in.