We’ve talked about this before, but I’m going to show you one more little “trick” that turns a good hem job into a great hem job.
First a quick run down on basic hemming. Try your pants on and have someone pin the cuffs at the level you want the pants to end up. On this pair it’s 2.5”.
Divide that measurement in half (1.25” on this pair) and measure from the edge of the factory hem that distance. Press all the way around.
Sew right up next to the factory hem. I like to start right before the most detailed side seam and make sure it’s lined up perfectly.
Go back to your ironing board and press the factory hem “down” and the part you just sewed “up”.
You can stop here if you want, but (especially after washing) you might find that the part you just sewed flips down and hangs out of your jeans or that your cuff flips up and makes the hemmed part visible.
Take your jeans back to the machine and stitch RIGHT on top of the seam line on both side seams.
And here’s a look at the other seam: