I put together a 5-panel painting for the church to be used during the season of Lent. Each one measured approximately 2'x7'. I constructed the frames out of 1x2 furring strips, a very inexpensive material available at your local big-box hardware store. Each frame has corner blocks and two cross-braces to ensure that they don't flex with the pull of the canvas.
Canvas is stretched over each frame and stapled on the back. You can buy cotton canvas at a fabric store, or save a bit of money and buy canvas painters drop cloths, the heaviest you can find, and cut them to size, avoiding seams. Each canvas is coated with gesso, a white acrylic coating. As it dries, it pulls the canvas tight and provides a uniform background to start painting on.
This is really a paint-by-number kind of thing. I choose an image and then project it onto the canvases, tracing with light pencil lines. Then I use gallons of tempura paint to add the color. I find it works best layering dark shades over light, and blending colors quickly, just a few brush strokes. They really looked sharp when we put them up! They were hung in the sanctuary throughout Lent. We manipulated the paintings in various ways to help create some interpretive possibilities during Holy Week. For Palm Sunday, we covered them in burlap and wrapped several strip palms across the front, the idea being that the events of the crucifixion are shrouded from our vision. Cloaks and palms obscure Christ's true mission.
For Maundy Thursday the coverings over all the panels except the Christ panel were removed. The events leading to Calvary have been set in motion, though the outcome is still just out of sight. That last meal that Christ shared with his disciples is a kind of protected space, the cross not yet intruding.
The paintings were altered yet again for Good Friday. The Christ panel was now fully revealed, while the other panels were defaced. The images were painted over, the panels entirely blackened. They appeared as holes in the walls, dark spaces that drew the eye to the cross.
On Easter Sunday, the panels were all removed, and the large cross at the front of the sanctuary received all the attention. These were a fun project and received a lot of attention during Lent.