Stain the Deck Surface
Staining the deck surface can be done a number of ways. You can use a pressurized sprayer (and deal with wind staining the side of your house) or you can use a brush (if you like to kneel and bend over for hours at a time) or you can use a large pad applicator (if you have a life).
The paint pad applicator does a great job in providing a nice even coating of stain and covers a large ares quickly. The only downside is the possibility of poor coverage in the cracks between the deck boards if you have a deck with larger gaps.
In that case you may have to use a brush to get the joints, wipe off the stain from the surface while it is wet, then use a pad applicator for the deck surface. Or since you're down there staining the joints by hand, you may just want to stain the deck boards too maintaining a wet edge. If you do stain the deck with a brush, use a 3" to 4" brush.