This article explains how to sew a common three-dimensional pocket with rounded corners. This kind of pocket is based on sticking the pocket flat, and the other three sides except the mouth are in the position of static sample line. Add some height vertically, and then we will have a three-dimensional effect when we look at it. First of all, there must be ready-made teaching tools, namely thread, cloth and sewing machine. Then we are going to walk together, then we are going to walk together, and then we are going to walk together. For the three-dimensional strip, we will fasten the patch with our mouth and then iron it with the three-dimensional strip. When finished, we will put the pocket strips and belt cloth together, and remember to put some cuts at the corner. Then, after the entrance is completed, we turn over the gap of the seam and press a 0. 1cm open line on the front. Then fold the three-dimensional strip, sew the pocket three-dimensional strip on the car once after the pockets are accurately aligned, and finally fix the bag mouth.