You should begin at the beginning, as they say. In deck construction, that means the foundation. Here, you'll pour the deck pad and secure the support posts. This base will support the whole weight of your deck, so you'll want to make sure your base is level.
Before beginning the framework of your deck, install some flashing along your home to shield it from moisture. Flashing is a water barrier of some sort -- anything from aluminum to PVC - that protects against wood rot. Check in your area to see what's recommended and available.
Next, add beams and joists to the posts you've planted in the cement. These boards are another support system for your deck: They distribute the weight and will anchor the rest of the structure as it goes up. Some building codes require joist hangers on each joist, so make sure you know your local regulations. You should also refer to your own plans to gauge the space you need between the beams, but the joists will be installed perpendicular to the beams.
The decking is next. It covers up the skeleton of bolts and boards and becomes the deck itself, the main floorboards. This framing is really the first part of the process that looks like a deck. If your deck will have handrails, add them here, making sure to stabilize them with balusters for safety and support . Does your deck design incorporate stairs? If so, you'll add them here, following your plans.
Once you've done the hard work, it's time for finishing and sealing the wood. In our next section, we'll cover some safety reminders before you get out and enjoy the fruits of your labor.