For a few jobs that I did in a print shop a few years ago I didn't use a 2D drawing programme which if I was in my own house I would have used. Using masking tape and rule I stuck the tape down around the top of the box the distance down that I wanted it to start, right around the circumference of the box. This gave me the measurements of the circumference and I also marked onto the tape the middle of each side, roughly the size of each corner and also the centre of the corner. I did the same for the bottom of the label drawing on the masking tape the appropriate centres and lengths. Knowing these sizes I went at that time I laid the first main side then drew a radii for both corners, top & bottom, had to accept that it was 1/4 of diameter, then tangentially to circles the sides, marking centreline. Then copied and pasted each corner and each side onto the correct position. The tapered box was for a local company who were marketing nails and the design was simple can't remember the size but it must have been around 350mmx200mmx150mm. Tried using the Arc Tool and using a percentage with length of the bottom cord over the top but this was inaccurate.