Hi there, one of my favourite (Australian spelling) subjects.
You will find on here photos I've posted previously of my old enclosures by doing a search. Here are a few of my recent addition since I moved house.
You may not want to build something like this but I believe there are few considerations that may be of use.
The basic elements are:-A barrier which the blueys cannot climb. Generally something 18 inches or so is adequate, preferably 2ft but the higher the more light will be blocked out. Lower barriers will also aid air movement/ventilation and prevent overheating in hot weather.
-A sunny position that gets at least 6 hours sun a day in the warmer parts of the year.
-The ability of the blueys to have soil contact as a means of helping them to regulate their temperatures.
-Adequate vegetation- this helps to provide shade and security for the blueys, also localised humidity levels which helps in shedding.
-A combination of rocks and hollow logs which they can move around, get under, or inside of.
-Generally barriers need to be dug in at least 10 cm or 4 inches or so and back filled around the trench with crushed stone or a couse concrete mix to stop them digging under (generally compacted stones are adequate, particularly if filled over the top with clay.
- Bird netting or similar (such as shade cloth over the top) - note that shade cloth provides shade so use strategically.

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- Something to provide shade, including a blind that can be put over the enclosure.
- Dog or other animal proof wire that can be integrated into the design, see from my photos.
- A lockable door.
- A mounded area for the blueys to sleep under objects such as logs, or other waterproof barrier (above where it is likely to flood).
Notes--pay attention to aspect (where is placed relative the the travel of the sun) during the warmer part of the year.
-consider planting edible plants such as strawberries, dandelions, aus native plants such as ruby saltbush.
-have a designated feeding area with overhanging wood or other feature nearbye that will make the blueys feel secure - make this near the door to make it easy to access.
- have designated pavers etc in the enclosure to prevent stepping on the blueys.
-Make the enclosure high enough so you can walk in it comfortably. If you don't then you wont go in there and maintenance will suffer.