I just added a shelf onset my desk with plywood and L brackets to hold it up. The hardware store can cut the plywood for you. I was fortunate enough to have a DH to cut the hole for my machine. If your machine has a top loading bobbin, you can cut the hole just big enough for your machine, but if you have a front loading bobbin, you will want a bigger hole with an insert to go around it. Sewing Machines Plus sells the custom cut inserts for $50-75 depending on how big you need.