A pavise that stops arrow fire can be made from cloth stretched over a frame of 1x1 lumber. Like most of the things we do, they are simulations of the actual article-wooden hoardings. Cloth pavises won't stop a ballista bolt, but neither will a pavise made of actual wood (the rule is that a ballista bolt destroys pavises and hoardings, and kills anyone behind them). So there's no point in making hoardings out of heavier materials, and cloth pavises are light, easy to transport, and so cheap that you can afford to burn them after the last battle and you've lost almost nothing.
      Just make a frame of 1x1's, about 3 feet wide (for one man) and 4 to 5 feet high - plenty of room to kneel behind. The corners can be screwed together or nailed. Cover the frame with heavy cloth - trigger or canvas - but don't stretch it tight. Slightly loose fabric will help absorb the impact of a shot. The fabric can be stapled or glue to the frame. If it is glued, press down the fabric while the glue dries, to make sure it permeates the weave.
      A cloth pavis is so light it doesn't require handles for movement, but they make it easier to handle while wearing gauntlets. To prop it up, I would recommend two short props, one on each side. A large central prop gets in the way when you try to move around behind the pavise.
      It shames me to admit Trimaris thought of these things first. At Gulf War VII, they had dozens of these things. Because of them, their archers could safely get in position less than 20 yards from the fort walls. Closing that range did wonders for their accuracy.