|I posted this yesterday and was encouraged to post it here. Since finding my way around this site is challenging for me, I hope I am doing this correctly!
The little needle is one of the biggest factors to stress free sewing and I don't try to sharpen them. Depending on the project, I change the needle. However, since needles are not free, I do try to reuse a needle used on small projects. I try to keep track of the needle size, type and usage time by clipping off a small swatch of fabric from the project, writing the needle size on the swatch along with a symbol like "U" for universal point or "J" for jersey, etc. I simply pin the needle through the swatch to a pin cushion. Next time I need a jersey needle for a tshirt, I can easily see needle size and type and automatically tell how long it has been used. I cut a swatch from the second project and repin the needle through both swatches again. If I see a needle with sticking through 4-5 (or less, depending on how much each project used the needle) swatches, I can throw away the needle with a clean conscience! This is especially helpful when I use stretch twin needles for hemming tshirts. They are expensive but used very little on each project. In that case, I will pin multiple swatches with a pin and try to pin the double needle through one layer only.
Since I do a wide variety of sewing, my needle cushion got a little crowded, so now I repin needles and swatches to a wall quilt by my sewing table! Hope this helps.