Summarize this article:

Bare wood always needs priming before painting as the primer acts as a sealant. When you are sure that the outside wood has thoroughly dried, use a top quality latex or oil-based primer and apply it to the entire exterior of the house.  Latex primer is an inexpensive, all-purpose choice. Bring your final paint sample when purchasing primer. Primers are usually white, but tinted ones are available to match your top coat.  Lay down a drop cloth to protect the ground and any plants in the area. Stir the primer well from the bottom of the tin to mix up all the solids that may have separated, and consider using a tray liner for your paint tray.  You can use a nylon-polyester brush, roller or an airless paint sprayer to apply the primer.  Start by priming the patched filler spots, then work your way down from the top of the outside wall to the bottom. Priming the patched areas first can improve the final paint job.  Let the primer sit for 24 hours to ensure it is completely dry. Now that the surface is properly cleaned, prepped and primed, it’s time to follow up with a great paint job. A good paint job protects your house like a raincoat. You can use a top quality 100% acrylic latex exterior paint as a topcoat - buy the best quality paint you can afford.  Before you begin, mask windows and doors with heavy plastic and once again lay drop cloths on the ground.  For primed, bare wood, you will need about one gallon of paint per each 400 square feet.  Use a nylon and polyester brush for latex exterior paint or a paint sprayer for a faster job. Always start at the top and work down so that drips are erased as you work. Follow the sun around the house as you are painting. Another coat or two will make your paint job last longer. While it may seem like an extra expense at the time, you will save yourself time and money on future repairs  by properly investing in the repair process now. If you can, you should always apply two finish coats, each within two weeks of each other.  After you’ve painted the body of the house, proceed to the trim, using an oil-based paint. Brushwork is best for applying trim tidily.  A good paint job will last for 10 to 15 years depending on the elements your house is exposed to.

Summary:
Apply a coat of primer to the dry wood. Apply the final topcoat of paint to the wood. Consider applying one or two follow up coats of paint.