Instructions
Find a Crafting Table in your home and right-click it. This opens a 3-by-3 Crafting Grid.
Fill the center row with wool. You can get wool by shaving sheep with shears.
Fill the bottom row with wooden planks. You can get planks by Crafting, using wooden logs.
Click and drag the image of the bed that appears into your first equipment slot, located below the inventory grid. Press "Esc" to exit the crafting screen.
Right-click wherever you want to place your bed. This is your new Spawn Point.