I would do it in three parts:
1. Cut the full blue square, then cut off the corner where the stripes will fit (don't cut it in half - just cut off the corner). This will waste the corner triangles, but they might be useful in the main block.
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2. Make a strip set of orange-blue-orange. Cut it into pieces.
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A ruler like this:
https://www.dinkydoo.com/collections...le-quilt-ruler might be useful, but the sketch above sort of shows how I would cut it using a regular square ruler. You might want to cut them a bit long, so that you don't have to worry about lining them up perfectly. Sew the stripes onto the lopped-off squares from step 1.
3. Cut white squares. Cut in half, and attach to the corner. Again, oversizing a bit would allow you to square up the whole block at this point.
By pressing the strips all in one direction at step 2, the pieces cut from opposite sides of the strip set will "nest" as well as seams can when they don't run parallel. You would have to press the white triangle seam in the same direction as the strip set for each block.
Let me know if this doesn't make sense... I could try to draw some better diagrams, if necessary.