This is going to sound really bad, but the only thing I can put triangles in my daily life in is when I'm sewing or cutting a pattern. When making a pattern, I'd use basic triangles to form the pieces of a garment. Since we are looking at triangles, the example are dresses.
For sleeves, which sounds a harder than what it is, I would make two triangles about the width of a baseball bat, and then make another triangle of the same size. Because, unless a person has the arms of a number two pencil, the sleeve needs to be sure it'll fit the wearer. Now, sometimes a person has wide arms (me), so the two baseball bat sized triangles are going to have to be made slightly bigger. Something like a wiffleball bat. Now, for the bodice, I use the reference of pizza slices, when measuring the chest, I determine that for me I'd use about two triangles about one and a half pizza slices big. Again, depending on the wearer, the triangles would have to adjust and be made more obtuse or acute. But those are the examples of my life where I would use the concept of triangles.
Looking at the different kinds of triangles there are, especially for this week, let's put some professionalism into this discussion post. For the sleeves, rather than saying the size of two baseball bats or wiffleball bats put together, the proper triangles I'd use would be scalene triangles. But, again, depending on the wearer of the dress, the scalene triangles would have to be adjusted to fit. And for the chest, rather than saying 'a slice and half of pizza', and since I realize that is a bad example to use - and I will explain why shortly - an isosceles triangle is what I'd use to measure the chest of the wearer because each bosom is about the width of an isosceles triangle, but since no one bosom is the same for the wearer, the isosceles would have to be adjusted. The torso to the hips of the dress I'd use an equilateral triangle or an obtuse because the female body has so many proportions to it, and the different use of the triangles help a lot with making a pattern.
Now, I said that I realize that a pizza slice is a bad example for an isosceles triangle and this is so, because a pizza slice is curved where the crust is and not only that, but a whole pizza can often be cut unevenly, so a slice of pizza may not have the angles that are in an isosceles triangle.
You can triangles in other areas of fashion besides dresses; such as shorts and pants, maybe even corsets- CORSETS.
I have a pattern to make a corset, and when I examined it, I saw some basic triangle shapes to it. Now, I haven't made my corset yet, but I have a basic design in my head of how I would design my corset, especially since I'm designing a pair of pants with it that has an attached cape. Why not? Go for the dramatic.
Especially when I have Disney villains stuck in my head, Belting out their songs of revenge and heartbreak and evil schemes.
Using triangles in fashion, as well as other shapes is quite easy. You just have to know how to look at something and see the shapes, and then you have to realize how to put the shapes together to how you want them to be.
The video above is a educational video of how to fashion a corset, but when you watch it, be sure to pay extra attention to the shapes used to the pattern making. Even though they don't look right like a triangle, that's just one example of making a corset using triangles- keep this professional, Aryal. Scalene triangles.
It's also not hard to imagine a design in your own head of what you'd want your own to look like. People who don't know fashion or design probably wonder where could geometry and shapes possibly be used (or maybe they're just watching Netflix and drinking soda pop. I don't know your lives. Yolo) well, ....fashion is a big place where shapes and geometry are used. Especially when measuring the angles for the perfect fit.
Also, designer tip: If you can't afford boning for the structure of the corset, use zipties. (The large ones).