To order, commission, or have something made/to arrange for something to be made to order.
結婚式のためにスーツをあつらえた。
I had a suit made for the wedding.
展示会のための看板を業者にあつらえた。
I commissioned a sign from a vendor for the exhibition.
願いを聞いて、彼があの席をあつらえてくれた。
He arranged (had arranged) that seat for me at my request.