Unless you’re using a 2-in-1 formula or painting over an existing coat of paint, it pays to apply a coat of primer ahead of your new paint. Decks see a lot of footfall and exposure to extreme and sudden temperature changes and moisture levels. The primer promotes better paint adhesion, moisture repellency, and a smoother finish, which means you’ll often need fewer coats of paint. 

Ideally, a gate should be able to swing both in and out. However, if it can only open in one direction, it is generally best for it to swing inward. This is often the safest option, especially for deck gates near steps, as you'll want the gate to swing away from the stairs. An inward swing also prevents the gate from opening into a public space, like a sidewalk, and can be more convenient when carrying heavy items like a wheelbarrow into a garden.

There are exceptions, however. The layout of your property may require a different approach. For example, if your property is on a slope, the gate may not be able to swing inward. You should also ensure the gate can open fully without colliding with any objects or blocking access to other areas. For a backyard garden gate where public access isn't a concern, the direction it swings is largely a matter of personal preference. Finally, always check your local building codes, as they may have specific requirements for which way a gate must swing.

In most cases, sanding an old deck before staining it is necessary to achieve a decent finish. If your old deck has a relatively new stain finish on it and you're only doing touch-ups, you can generally skip the sanding part. However, if your goal is to make the deck look and function better, sanding first is a must. 

You can nail or screw composite decking, but 3-inch decking screws are the better fastener choice. Unlike nails, decking screws won’t back out of the composite material over time. There’s also little danger of splitting composite material when driving screws, so you don’t need to pre-drill holes unless otherwise recommended by your decking manufacturer.