Making the best use of small spaces is what RV living is all about. One of the best ways to utilize space is to build a folding table. It can give you the counter space you need and then be put aside when not in use.
Measure the area where you want to put your folding table. The space should include a wall, since your table will fold against it. Transfer your measurements to your plywood, then remark the board, making a square 4 inches smaller all around than your original measurements. This will allow space to get in and out from the table.
Cut the square out from the plywood. Sand the edges.
Cut the two-by-two so it is 4 inches shorter than the width of your table. Lay your table top on the floor against the wall and mark on the wall where the outside edges of the table are (call this mark "A"). Put another mark where you want the top of your tabletop to be ("B"). Put a third mark 2-3/8 inches below that mark (mark "C").
Hold the bottom of the two-by-two so it is level with "C" and its ends are 2 inches inside the outside marks of your tabletop ("A"). Attach the wood to the wall using wood screws and a drill. This is what your table top will rest on.
Lay your table top on top of your two-by-two. Make sure you are lined up with "A" and draw a line on the underneath of the table that traces the edge of the two-by-two. Remove the table top and attach one side of the piano hinge to the bottom of the table, using the line you just traced as a guide.
Lay the table top back on the two-by-two and attach the other side of the hinge to the two-by-two. Your table top should now be able to fold against the wall.
Hold the table top up as if you were going to put it in place and measure down to the floor. Cut a length of two-by-two to match that measurement, and then cut two additional pieces 12 inches long. Attach the two shorter pieces of wood to each end of the longer one so they are flush to its end and it is centered on the cross pieces. It should look like a capital "I" when you are done.
Attach one end of your second piano hinge to the side of one of the cross pieces so the hinge part is flush with the top edge. Set the leg underneath the table so the hinge is 4 inches in from the edge of the table. Attach the other side of the hinge to the underside of your table. You now have a folding table in your RV.
Cut your Formica to fit the top of your table. Apply epoxy to the table top and the backside of your Formica. When both are tacky, press the epoxy sides together and your table is done.