A pergola is a great way to add extra shade and a wonderful feature to compliment the rest of your landscaping. Before you start building your pergolas there are some essential steps that you should follow:

• Check the regulations. A quick trip or a phone call to your local council will let you know what you have to do in terms of paperwork and compliance. Failure to consult with your council and notify them about your plans could mean you have to pull your pergola down at a later date.
• Can you build it? If you are not so handy with building and home renovation, then you will need to obtain quotes from experts. Even if you can build it yourself you will still need to assess material costs.
• Location of your pergola. Start deciding where you want your pergola to go as this will affect the dimensions as well as shading. Remember, your pergola may create extra shade over existing plants so make sure you check if they will need to be moved.
• Budget.  Have a clear budget set out and make sure it is realistic. It may cost more than you think and you will want it done properly the first time.
• Size matters. Once you know where you want your pergola, choose a size or have your builder recommend one for you.
• Materials. Lastly, you will need to choose what types of materials you want to build with. This will include steel or wood frame and selecting the type of roofing of your pergola.

Source: http://www.homeimprovementpages.com.au/article/6_steps_for_the_perfect_pergola