This is one of those things that you never know you need unless you have one. This amazing wooden sofa sleeve works perfectly on either or both sides of a sofa set. It gives your sofa a nice look. The sleeve can also be modified to include a cup holder, mobile holder, etc. You can easily find this item on any online furniture store, but an even better idea is to build one. This way, you can make a sofa sleeve design that you actually like and make space for cup and other things.
You can also use Google image search to research a project. Unlike the PDF search, the image search provides a photo of what the project will look like, which is helpful in determining if you want to pursue building it. By doing an image search for how to build a step stool, you will have a ton of options that all lead to woodworking plans of various quality. (The how to part of these is important—otherwise you’ll just get pictures of step stools.)