Lots of people tell me they want to sew, but they don't know how to use their machine. I can relate! It took me forever to learn that it mattered which way the bobbin went in on the machine. But once I figured that out I was off and sewing. I recommend this video class.
Claudia Miller goes over threading, bobbin winding and insertion, and many other little details to get you sewing. And best of all the class is free! Its free to register there, too. But you do have to set up a free account. There are many other free classes in other crafty topics, but I haven't looked at them.
Once you "buy" the free class it is yours to watch as often as you need. Plus, you can ask questions and get help as you go along. You can have your machine next to the computer and go through it with her, pausing if you need to.
If you are looking for a sewing book to get you going successfully, I recommend The New Complete Guide to Sewing: Step-by-Step Techniques for Making Clothes and Home Accessories Updated Edition with All-New Projects and Simplicity Patterns (Reader's Digest). Take a look at the used books for a better price.
Sewing is such an enjoyable hobby for me, I want everyone to be successful!