To the drummer, a drum riser can be a key element in a live performance. A riser serves as an extra platform to provide visibility for the crowd as well as for the drummer. In some small clubs and venues, these risers are not provided, so it can be useful for a group to have a riser that can be transported with the rest of the necessary gear in a van.
Take one of your sheets of plywood and mark it into two 4-foot x 4-foot sections. Take your circular saw, and carefully cut along the line you have created. Do this with the second piece of plywood as well.
Take your carpet remnants, and with your utility knife cut them into 4-foot x 4-foot sections. It easier to cut the carpet if you cut it from the webbed backside.
On your pieces of plywood put an even zigzag bead of liquid nails that covers one side of the wood. Take your carpet squares, and line them up on the liquid nails side of your plywood. Run your hands over the carpeted surface with medium pressure to avoid any puckering or bunching in the carpeting as well as to assure maximum adhesion. Repeat this for each piece of plywood on each side. Wait an hour for liquid nails to set before moving onward.
Take two of the carpeted squares, and lay them butted together, as if they were the original sheet of plywood. With your drill driver attach two of the hinges at even intervals along the seam of the two pieces. Do this also with the other two carpeted squares.
Place your five-gallon buckets in three rows of three creating a 7-foot x 7-foot square. The buckets should be upside down (widest portion on the ground) and equidistant from one another.
Place your first hinged piece flat across half of the buckets, hinge side up. Butting the second hinged piece flush with the second, cover the other half of the buckets.
This should create an 8-foot x 8-foot carpeted surface that is equally supported by the buckets. The carpeting on both sides should prevent any kit movement from the force of the drummer. It will also prevent any movement between the bucket superstructure and the platform top. For aesthetic value, consider painting the buckets black or to match the carpet colour.
Use short thread/weave carpet, so carpeted pieces will fold up easier. For a shorter platform, evenly cut buckets to desired height.
When working with saws of any kind, be sure to wear proper eye protection.