Before ucpcyling something, it is best to try to fix it first. The time for upcycling is when they are beyond repairing or fixing. If you have kids, this looks familiar:
I know that many pants end up to the trash bin when this happens (I have done it myself) but what a waste of money and fabric! I know it isn't fun and of course you need to have sewing machine and time. Which I know that many people lack. But even then you can buy iron-on patches, those won't take time that much. So if the pants are worth saving (i.e. there is nothing else broken or stubborn stains), at least get a package of those and you have saved quite a bit of money and nature. Patching isn't my favourite thing and I usually keep postponing things like this. There just isn't the same feeling as in creating new but there were four pairs of these and all of them of course my daughter's favourite leggings. The choice of what to wear had become quite limited for her so it was time to do something for it.
Of course there are several ways to patch the knees but here is how I do it. First I ripped the seams because I sew the patches on with sewing machine. Notice that the pants have over stitches on inner seams so naturally I ripped the outer seams. How you rip the seams is up to you, depending what way you prefer and of course what kind of fabric and seam you have. These pants had over-lock seams and the needle threat was nicely loose so I cut only the both needle threats between couple centimeters and pulled them away, the rest became loose after that. If you have tighter seam and harder fabric you can always use the tip I mentioned in Bedside pocket for loft or bunk bed.
I ripped just enough to get working space for the patching, in this case something like 20-30cm and I left the bottom of pant leg untouched to avoid the extra work of ripping that too and then sewing it again. Even you left it untouched, you still get enough space to sew.
For these pants I wanted to add nice patches out of scrap fabrics and I didn't fix the hole in anyway, I just covered them as they were rather small. I started by choosing the fabrics I was going to use, measured how big the patches should be, draw the form on the fabric and cut roughly around. Then I ironed them to bondaweb (double sided adhesive) wrong side facing the bondaweb's glue-side. Protect your iron by covering the fabric and bondaweb (fabric and glueside up) by covering it with baking (parchment) paper. You can also draw on bondaweb as one side of it is paper, but I wanted to know the scraps were big enough and that the images in fabric would be in correct places. With bigger piece (or one without images) of fabric you can draw on bondaweb, cut that roughly and iron it on the fabric, then cut it.
So after ironing it looked like this:
The markings on the fabric show nicely through the paper. Now I cut the patches out following exactly the lines I had marked. It is much easier to cut the patches now after ironing and before taking of the paper as they are more solid now, no wrinkling or rolling. Also if you cut them after removing the paper you are in trouble because they are sticky and it is difficult to get the edges neat as glue is quite hard to cut... I have tried it so just warning you. After cutting, peel of the paper like this:
Then iron again, this time the patches on the pants. Now it looks like you have patched the pants and can just close the ripped seam but don't! The bondaweb won't hold the patches on in use, especially not in a place like this. So after ironing, sew around the patches. Now you can close the ripped seam and you are done!
There, four leggings ready to be used, looking even better than they did before!