Greetings to all. Now, we are going to go over some useful tips for 3D modeling. Let's get started. Before modeling, there should be an environmental setting including a layer managements and group making. While we start to create models, we should know some tricks, such as snap checking, how to hide lines and to make lines perpendicular for each other. Don't forget to check your model whenever necessary. A building usually includes several floors. We can separate a building model into parts because it might be too large to edit if we put all parts in one file. It will be advised that we save each part of the building including raft foundation, basement, first floor, typical floor, and a penthouse as file respectively. Raft foundation means the foundation of the building. Then we can assemble these files into the complete building model. In each file, we create layers to manage objects. We know that a building consists of units of structure, such as columns, beams walls and slabs. Creating layers for each units helps us manage models. Just like that, we arrange first floor and a typical floor in different files. This layer zero, we generally don't use this layer. In floor plan, we import the plan of the building we will develop, so we can hide it if we need to. Besides, first floor slab, columns, walls, stairs and handrail, all have their own layers. In practice, we assign different colors to different layers for better management. It's crucial concept. In this course, they are simple colors, however, in practice, the amount of colors will confuse you including structural colors, decorative colors and so on. Next, we show master how to make groups of objects. Turning entities into groups helps to manage units separately and simplify the modeling process and avoid troubles. Likewise, making entities or components benefit us more. It saves time on drawing and reduces size of SketchUp file. Now we take a window for example, when there are many same windows in the model, we can just insert the same window components many times instead of drawing the windows repeatedly. Meanwhile, the size will not increase when we insert the same component, because insert a component is like we just mark a reference on the file. All the entities of the window of this won't be recorded again. On the opposite, the entities of the window will be recorded again and again as we draw the window repeatedly and the size will increase without doubt. Now, let's go over some important concepts while modeling. First, the coordinate axis can help us make lines perpendicular to each other. Line entities in building models are basically perpendicular or parallel to others. In SketchUp, it's easy for us to draw rectangle object by following the red, green, blue axis. For example, when we draw stairs, we can follow axis to draw steps and the landing with ease. If one line is parallel to green axis, the line turn green, red and blue lines are the same. If the line is black, it means that the line isn't parallel to any axis. Well, we can't make a line parallel, we can move the cursor further from the start points. When the line turn to the colors we want, now we press "Shift" and snap the direction. To sum up, to press shift is an important tool to keep line parallel to any axis we want. Second, we can ensure lines are connected by snapping at end points of them while drawing. Without connection, lines cannot generate a face. We need to be careful that the line we draw start from the correct position. In SketchUp, we can snap the endpoints, midpoint, and intersection of the lines. While we hover a cursor on the points we mentioned, it will be snapped automatically. It is a very useful function. If we cannot snap the points we want, the object we create might be far from our imagination. For example, in mind draw a line that seems connected to each other but it actually is not on the right position, thus, there might not be the face we want to create. You will be pain-taken to find these small errors in 3D. We have to better snap the point correctly in the beginning. After completing the model, there might be some unnecessary lines. We should delete them to make it pleasing to the eyes. Sometimes we might not be able to delete the lines, in this case we can right click mouse to hide it. Briefly, remember to hide unnecessary lines after drawing. Lastly, we must check the model we are creating during all the models in processes. Because we can only see one or two faces over the model to remodeling, we should rotate and check it continuously. The earlier we find the error, the easier we fix it. When there are many entities in a model, it's harder to fix errors. Moreover, it might generate problems or chaos. The best solution of this situation is to redraw the model and you will form more backup files. According to our experience, to redraw the model is always faster than to fix the error in a model. We might find the error half an hour after starting and then we have two choices, one is to fix the error and the other is to redraw. If we would choose the first, we might redraw the model within 15 minutes because we already know the process very well. If we choose the latter, it might take you more time if the problem is complex. Thus, when the problem is too complicated to fix up, redrawing the model is a better option. Of course, always checking and fixing the problem early is the best thing to do. Today we learned some useful tips for 3D modeling. Now we know how to measure the model we create, how to speed up the whole modeling process and how to avoid errors. We are equipped with all the necessary knowledge for modeling a building, there is a lot worse on the next video, but let's rest a bit. Goodbye.