I have resisted responding to this because it might hurt some feelings, though I'm not implying Gandolf50's feelings will get hurt because I know he's one of the sharp knives in the drawer.
If you have some kind of burr on the scissors, the foil might knock it off and the scissors will appear to be sharper. I saw someone suggest that, if this works, cut some fine sandpaper and see what happens.
If the scissors have the proper shape, they are sharp. From here, honing may be in order or probably stropping. This is the process for any knife and it can't be avoided.
To "sharpen" or hone your scissors, you can use a fine stone, ceramic rod, or abrasive paper to refine the edge. Make the flat side flat and on the bevel side just restore the bevel. You will raise a burr if you do this right. You can get rid of that burr by cutting something with the scissors. Stropping on leather with some abrasive on it, I just use rubbing compound, will also clean up that edge.
Now, if you are using cheap scissors, and I consider Fiskars to be cheap, the edge isn't all that good to start with. You want to see some good scissors? Visit the sewing world. Dressmakers have great scissors. The embroidery world has some awesome scissors. They are steel and have good edges. You can clean up these scissors and they will last a lifetime. With embroidery scissors that don't fit your big hands, remember they are made to be used with the finger tips.
Surgical tools are not good knives or scissors. They have a metal that can be sterilized. They are disposable. If that is all you want, have at it.
I hone my scissors and knives all the time. If they aren't cutting beautifully, you are wasting your time. A few seconds honing or stropping and they are great again. If you notice a huge difference, you waited too long to hone or strop. It's easy and quick so do it often.
Hobby knives are disposable. My hobby knives last forever because I only use them for scoring metal. Again, they are disposable. When I get a hobby knife, I spend some time with the stone putting a proper edge on it. Oh, and they make good scrapers. They are also good for making custom edges, kinda like those Zathros toolmaker folks.
If you want an inexpensive knife that is pretty good, check out Morakniv. They make some hobby carving knives that are pretty good and low cost. They come wicked sharp. You may notice a pool of blood on your model. That came from unknowingly getting cut by those things. Guess how I know that. Amazon sells them.
Investing time in learning to properly sharpen, hone, and strop a blade is time well spent. It is not hard. You will fine you can eventually get great results without using a guide. You don't need a lot of fancy tools but you do need a leather for stropping and a fine stone, I use ceramic, for honing. If your edge gets ruined or you are trying to restore some old knife, you will need other grits to restore the edge or sharpen.
Knives are made so you can put on the edge you want. Their handles are made to be modified. Make them fit your hand. Put on a guard if necessary. You can use tape for that. A round handle rolls, so get rid of that roundness. When it is round you have plenty of material to make it fit a right or left hand. Don't just leave it like that. Make it yours.
Okay, I'm done. Sorry for the long post.