Cut your board into two 2 foot boards and three 2 1/2 foot boards. With the miter saw.
Use the table saw to cut your boards to a 6" width.
Try out different kinds of stains on scrap wood. Choose the stain you want to use.
Use an old rag to stain your boards.
Use a brush to apply polyurethane.
When your polyurethane dries you need to whip your board down with steal wool to smooth it out.
You are now ready to screw your board together. Use clamps to hold your board together when you screw it together.
You are now finished with your shelf. You may use it to put pictures or things that you collect no it, it is a great thing to have. Enjoy.