example: in level 3, eat the fruit and move your head past the bottom right corner of the mainland. then tap left and up quickly in that order. you'll end up facing up, with your head on the target. then press x and left at the same time and you'll end up facing left with your head above empty space. then move left, press x to resolve the target on the right
in level 5, you can have a 2-length snake with the tail on the right target, head facing down using the same trick, and pressing x with two left keys (i use wasd and arrow for this) allows you to jump past the target, leaving you with a straight 3-length snake