After you have completed repairing or installing your drywall you will need to sand and prepare the drywall compound used for taping joints and filling nail or screw heads.
Sanding is only for the final prep of the wall and for the most part won’t be needed while making repairs.
First start by working your way around the entire room with a drywall pallet knife knocking down any big bumps. Hold the knife at a tight angle to the wall and rub it in one direction making sure not to cut deep into the compound or drywall outer paper.
There are a number of vacuum attached sanders on the market that will work with many different shop vacs. They are a decent choice but can often take more time then just using a regular pole sander.
You should never try to use an electric sander for finishing drywall compound. If the area is very small do it by hand if you are working on a whole wall, room or house then hit the gym and workout… but using a motorized device to work with drywall will definitely kill the tool very quickly.
Pole sanders with a vacuum attachment are useful for reaching ceilings and walls in vaulted rooms without a ladder. When using a pole sander you should take care to inspect your out of reach work before applying paint so you do not end up with surprises.
For lower work you can use a sanding block which is better then doing with only your hand because the block will help you level the area.
What type of Sandpaper?
Sandpaper can actually cause you problems. If you are working with a paper with an metal content you can end up with spotting or staining.
Sandpaper is also very quick to fill up so it should only be used if you are repairing small areas.
Sanding Screens are made to be attached to a drywall sander and although they will also clog they are easily cleaned for longer use.
Screens will come in a variety of sizes but it is best to get pre-sized screens because they are easy to apply to your sander with out the need for measuring and cutting while you work.
Your final cleanup should be done with a moist not wet sponge or towel. Personally I prefer an old bath towel which usually has a terry side and smooth side giving you even more control of the final finish if you need to remove a few sanding scratches.
Once you are done you want to wipe the full walls and ceilings down and vacuum as much debris at the base of the walls before you begin to apply your primer and paint.
Primer should always be used over drywall compound and on new walls. Not doing so will result in waste of your top coat paint as it will be sucked into the paper and plaster.