As soon as I came across this tutorial, I didn’t wait any longer to start building one. Some of the items you need for this project are hardwood plywood, saw, glue, nails, drilling machine, etc. The video is very easy to follow for anyone with basic woodworking knowledge and experience. The first source link also includes a step by step procedure in plain English for those, who are not comfortable enough with the video tutorial.
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.)