1. click on the money 2. click on the money again 3. click under the wherly bird to get the brick 4. destroy something with the brick 5. buy the level 3 fuel booster in the bonus shop 6. buy the level 1 pheanix feather in bonus shop 7. click the penguins beak in the main menu 8. click the meadal
For 5, I think you just have to get to high altitude and run out of fuel. For 6, I think you have to crash into the ground really hard. I completed all of the secret achievements without buying something from the bonus shop.
