Unlock outfits:
To unlock a male vest and female tank top, at the “Fashions and Grooming” screen, pause the game and press Z, Z, A, Z, 2.

Cheat Gnome:
To spawn the Cheat Gnome, while on a lot press B, Z, Up, Down, B. You
must then search for the Cheat Gnome on the island. After finding the
Cheat Gnome, the following cheats can be activated by pressing the
corresponding sequences of buttons:

All motives – MINUS, PLUS, Z, Z, A.
All plans – PLUS, PLUS, MINUS, MINUS, Z.
All crafting resources – A, A, DOWN, DOWN, A.
Max food/resources – LEFT, RIGHT, LEFT, RIGHT, A.
Max relationships – Z, PLUS, A, B, 2.
1 skill – 2, UP, RIGHT, Z, RIGHT.

Abducted by aliens:
Go to Crystal Island and send an SOS using the radio. Aliens will abduct you, give you a can of alien food, and drop you off.

Easy skill points:

To easily gain skill points, create an account with cooking as their main skill. Then, level up their cooking skill to level 6. Then get level 6 mechanical. Enable the “Maximum current food and resources” and “All plans” codes. Next, make the metal stove. Cook something random and eat it. If it increased your skills, open the screen and select “Island Travel”. Travel to another part of the island. You should now have the raised skills permanently. Repeat this process to get 10 of every skill, so that you can build a bungalow, bathroom, shower, marimba, and a better bed.