And all these matters will be set forth more plainly hereafter. Your Array First, examine your harness. Few harnesses conceal enough of blue jeans to hide their essential nature. Dark sweat pants, with socks in a matching color, are better and hose are better still. Two-tone Nikes don't look very medieval.
All black sneakers are better, and medieval shoes or sabattons are better still.
The right covering can conceal a multitude of sins. Essentially, you have two approaches. Before 1350, the armor was less challenging, but the surcoats were usually sleeveless, so they covered less of it. When sleeves were worn, they were rarely longer than elbow length. After 1350, the armor was more sophisticated, but garments called jupons or coat-armors, often with long sleeves, sometimes covered much of it.