Measure the building envelope of the property that you own, and desire to build a post and beam style home. This will dictate the size and shape of the footprint of the design. Learn all the setbacks and regulations that apply to the property, then create an exact footprint of your building site on graph paper, to scale.
Preview a variety of post and beam arcitectural renderings online or through an architect to get an idea of style, materials and time of completion. This will help you decide how big your want to go with your home structure, and how long it may take to complete.
Design your initial architectural sketch with framing elevations from all sides of the structure. Use graph paper as you execute exact measurements to scale. This will be the foundation of your design, so make sure that the plan is accurate from all angles.
Create a framing plan of each floor above foundation level. A framing plan is a topical view of the roof, from the floor level up to the top height of the roof pitch. Include the layout of rafters, ridges, trimmers and joist headers to complete a framing plan.
Identify the bent layouts of the roof structure as necessary. This will define details of cross-sectional locations, which is vital to proper construction, moisture runoff and sun exposure to the windows directly beneath the roof.