The first step in making an architectural model is to plan well. You need a clear goal, you need to know what the purpose and meaning of your model is, and you have to decide what you're going to focus on. Almost no one has the money or time to make a model that tells everything about the proposed project, after all. This is why you'll need to choose a particular aspect of the design to focus on in the model. For instance, buildings should use a model that shows the form, layout, and context of the building. That allows your viewers to understand the project instantly. Discuss details like materials and colors using swatches, photos, and drawings, instead of trying to include them in the model.
This isn't the only approach you can take, however. Some people choose to use the drawings and other supplementary materials to give the general idea of their projects, and use the models to help viewers visualize specifics. You might make a model of very interesting parts of the building, create a sectional model that shows room layout and organization of space, or choose a model that will show a tiny segment of the building in great detail. It's all about the goals that you have for your project and the best way to show them.
Once you know what you want to demonstrate with your model, it's time to pick the right scale. This will be affected by how much detail you want to show and how large the area you want to model. For site context models and others that show a large area, scales as small as 1:1000 may be appropriate to keep the model from being too large to move around. Of course, detail is often lost in a scale this small. If you want to show off the building without context, a scale as large as 1:100 might be chosen, which will allow you to show details like balconies, doors and windows. However, even this isn't large enough for lots of detail - scales as big as 1:50 and 1:20 are required for that. You'll generally need to show just part of the building in this case.
You also have to be realistic about your resources. Think hard about the facilities, materials, and time you have. You can't make the model show everything or you'll run out of time, fast. Many students with well-developed model making skills get bad grades because they don't bother finishing their models. It's hard to get the balance right, but it's usually better to use a less ambitious model and do a really good presentation than it is to have a great model but a slipshod presentation.
