Dot, you can work with moldings using simple tools. I would think that your first order of business would be to go to the library or bookstore and get a book with plenty of pictures on how to do it. It just makes sense to describe a visual process with pictures. Then check the posts below as there are plenty of tips and techniques about moldings.
By the way, for outside corners, you miter. But for most inside corners, you cope. Coping is an offshoot process that starts with mitering then used a coping saw to complete the fit. I noticed Ryley doing one on one of Bob's shows this weekend. Henry