Okay! So as you can see I've done the first pass on this bench with the course sandpaper and now I am going to do a couple more with the medium sandpaper and the fine sandpaper to prep it for the stain. Some times finer corners will also take some hand sanding that needs to be done. You can just use a little piece of sandpaper that is left over. When preparing the wood to be stained, usually using a fine sandpaper of 150 to 180 grits is the highest grit you need to go to. However if you are using a water based stain, you will want to use extra fine sandpaper as the final pass before beginning to stain.