Step 1: Find the game's directory on your hard drive. Inside, there will be a folder called "ICTDATA". Inside of that folder is a file called "config. Ini". Copy this file and paste it somewhere safe. This will be your backup. You must have this or the game will refuse to work in the future.
Step 2: Run Ice Cream Tycoon. The game must be running for this to work.
Step 3: Minimize ICT by either hitting the Windows key or Alt+Tab.
Step 4: Go back into ICTDATA folder and open config. Ini with NotePad. There is a line that reads "Cheats=0". Change the 0 to a 1 and save the changes.
Step 5: When you maximize the game again, you will now be able to activate the following cheats by pressing the following F keys:
F1 = $5000 for each time you press
F2 = All trucks purchased and added to fleet
F3 = All ice creams unlocked and purchased at 75 each.
You can press F3 again at any time to refill the stock to 75.
F4 = All neighborhoods unlocked
*Once you quit the game after enabling cheats, you will not be able to open the game again unless you restore the config file from a backup. Simply restoring default values will not fix this problem. Keep an original backup at all times.
*You must repeat these steps every time you want to play with cheats.