Keep the lowest segment in full sun. Fertilize well and let the top grow for another year or two. You could half the new growth in the first summer, to help the lower branch gain strength. Once you see strong candles there, reduce the top growth over time once the bottom gains strength and build your tree from there.
Aternative is of course to go literati, but the tree will take another decade to show sufficiently rough bar to make that look realistic. Can be done though.