These pants are actually the second pair of pants I made from copying my old favourites. The first pair, I didn't take any pictures of the process, or any notes. I wasn't sure it was going to work. LOL. I really, really needed dark brown pants. This was the only suitable dark-ish brown I could find. Not quite what I wanted, but they've worked out well with a couple of the tops I've made.
One important note. My original pants had a remaining seam allowance of 1/2" and both lines of top stitching were on that seam allowance. When I serged my seams, I did it at the 1/2" mark...but my remaining seam was much smaller so one line of my top stitching was off the seam allowance and looks different than the line that is on the seam allowance. On the next pair, I opted to serge the edges either before sewing together on the regular machine at 1/2", or I just barely skimmed the edge of the fabric as I serged the parts together at 1/2". Just enough to trim raggedy edges. It was a lot of back and forth from sewing machine to serger, but it wasn't too bad.
PS: I didn't go into much detail about how to copy YOUR favourite pants. This was more about copying MY favourite pants. The important part though, I didn't document. Taking apart your original pair. I know lots of DIY sites say to just lay them down and trace around, but I wanted to be accurate! And my originals had become unwearable, so why not take them apart?