How do you make a sprite move in circles and forward?

I know how you make a sprite move in circles. You make it move in waves forward and make it change direction after one way and you got a circle movement. But this only makes the sprite move in circles in one life not forward. So how do you make a sine sprite move forward.

Here's one way

Every tick

Sprite: move forward 100*dt pixels

Sprite: rotate 10*dt degrees clockwise

Sprite: set X to self.x+50*dt