This is a pattern where you can switch between colors as you like. Also you can try-out the different kind of color switching.
First the most common way is to just use the new color.
The second way is to finish the last stitch with the new color.
The tirth way is to use color 1 as the base and finish every stitch with the second color. This one results in clean lines but with more effort to achieve it.

It is also a pattern where you could use after every row a sl st and start with a ch.

You can also make a longer one and put a face on it to make it more fun.

This all are options you can chose. I will give you the basic pattern in one color.