Just putting it on top. Should there be anything put between the original desk and this top?
The plan is to use some cutoffs to create a 'frame' so it cannot move (3 hidden sides) and also to then create essentially a clamp under there as well so it is reasonably stable.
This is not meant to be furniture quality, just nice and large enough for me to enjoy in my basement office and to support multiple computer monitors.
Thanks to all for replying to my original request. Decided on using the finish from the above link (ENCurtis - youtube).
Not as many choices of woods around here as in large cities, I went with a cherry plywood, and the edges are a simple D shaped pine trim. After starting and making mistakes along the way, needing to sand it back down to bare wood and restarting, I got the top done. The trim pieces were a challenge as I 1) have never done any woodworking, so 2) have no tools, materials, or experience. Went through 6 different test pieces to get them finished. Since the trim is made of pine, the grain was very different than the cherry, so any finish that brought out the grain just made it look disjointed. Ended up finding Polyshades and that was what worked for me.
Next summer, will try to make a keyboard tray for this desk... Wish me luck!