Before finally deciding on a structural layout for your garden consider the idea of dividing up your green space into a series of Garden rooms.

Even the smallest of green spaces can de divided into smaller sections, which can instantly create interest and provide the illusion that the space is actually larger than it really is. The larger of our green spaces allow the garden designer to create intriguing surprises by dividing the green space into many garden rooms, each with differing styles and themes. For example one can be lead on a meandering voyage of discovery through elegant formal gardens, formal vegetable gardens, quiet seating areas, wooded walks, peaceful courtyards to, maybe, an orchard or olive grove with a whole host of wild flower shades growing between them with secret meandering mown paths that lead somewhere else!
The art of garden design is to combine natural materials with natural physics to create natural beauty and generate interest within any kind of green space. By using our knowledge of horticulture, natural physics and mathematics we can really achieve some amazing visual effects in our green spaces, like making spaces appear larger or smaller with the correct use of scale, or paths to appear longer or shorter. By using reds at the beginning and lavender blues at the end, and vice-versa, we can create the illusion of a longer or shorter path.
Dividing even the smallest green space into separate garden rooms, or areas, will automatically create intrigue, interest and will allow one to address and express any horticultural whim from gravel gardens to water gardens or from woodland glade to flowery mead. All this can be expressed in one large green space, one can create many interesting gardens in one, but also maintain a unifying theme throughout the design.
These garden rooms can easily be created using hedges, walls and fences as 'walls', or they can be divided more simply by using trees and evergreen shrubs. Simpler still, one can just create 'rooms' by means of mown lawn areas inside a wild flower meadow. Some areas within a garden receive more sun than others and some areas can be boggy and so forth. A garden room can be styled around the personality and feel of any particular area and should highlight and compliment the identity of that space, i.e. a small, shaded wood can be come a room for bulbs, ferns and other woodland plants. Whereas a south-facing rocky slope could become a Mediterranean area, planted with sun-loving plants such as Agave or Opuntia and various succulents or Mediterranean shrubs, which will clearly provide an exotic, arid feel.
Understanding the identity of any green space is fundamental when designing gardens, however this fact is often grossly overlooked, resulting in shade/moisture loving plants being planted in hot, sunny and dry areas. Consider for one second... how can balance and harmony be achieved in the garden when such simple rules are not followed?