First make a square...

Next cut out a piece from the left  and drag it to the right...

Now cut out another part  from the right and drag it to the left...

Now select the middle section and rotate it 90 degrees.

Now scoot the pieces together.

You'll need 4 of them, so copy and paste until you have all 4.

Color each one a different color.

Now piece them all together.  You'll have to rotate 3 of them to fit them together.  Rotate one 90 degrees, and one of them 180 degrees, and one of them 270 degrees.  (Notice any pattern with these numbers?)

Now copy and paste a bunch of them together to make a tesselation.