1. Download the practice save file from the Ressources page.
2. Go to C:\Users[Your user name]\AppData\LocalLow\Triple Topping\Ynglet
3. Unzip the practive save here. Make sure it's called Settings.yng
4. Remove the Settings v2.yng file, if it's here
5. Launch the game

Once you've done it once, you will simply need to first remove Settings v2.yng and then launch the game in order to load back the practice save. By default, the difficulty should be Too Difficult on the Story World and Challenging on the Bonus World but you can change the saves's difficulty in the pause menu whenever you want.