Assuming, as you said, that you want to do it on one foundation.
You need to split #2 into two pieces as you can't piece a shape like that.
So it would be 1, 2A, 2B.
Just draw a line splitting that alcove off.
And the current 3-11 positions need to be reversed.
After you do the 1/2 section, then you'll have a straight line to add the next piece to the left (currently 11 but should be 3).
There really isn't a #12 like you have as it would already be pieced.
The last strip on the right can be added anytime after the 1/2A piece is sewn.