Open and close the scissors as you find them.
If there is any bumping or snagging as the blades pass each other this means you have nicks or burrs on one or both edges.
A burr on one side of scissors dulls a spot on the other.
There are scissors so trashed that hand sharpening is going to be very time consuming and may not be worth it but they are valuable for practice.
Like a knife, look at the scissors edges to see what your starting with. What I look for, using good light, are flat spots or dings on the edge. See what these look like before starting. Repeating myself? yep. read this again.
So if there are nicks on the scissors edges we need to start there first.
I said no bevel on the inside of the edges. That is an exact statement.
That said, we need to carefully and lightly re-flat the inside edge of the scissors to at least straighten out the burrs or nicks. I like to do this before starting any work on the main sharpening bevels.
Open your scissors as far as they will go. Figure out how to grasp them firmly with one hand (and the holding hand can rest on bench/table or knee) DO NOT CLOSE SCISSORS UNTIL LAST STEP OF STROPPING. Please.
To clean up inside burrs place the stone on the back of the blade then rotate it to the edge until contact is just made. This is the only angle for cleanup of inside edges on scissors.
Get a feel for this.
Do not roll the stone off the end of the tip when doing this lapping.
Go slow and careful. Do not over do this, as soon as a good flat is perceived, quit. By flat, I mean hairline width flat along the edge of blades if hollow ground and flat ground blades do not need material removed from surface, only enough stone work to make burrs as flat as the blade...
Hope this makes sense.
*Hand sharpening scissors is a bit tricky in the handling and care needs to be taken as you go to minimize the draw down of the band-aid supply.*
Reason scissors remain open for duration of all sharpening steps is because we do not want any burr at the edges from sharpening process to collide with the burr on the other side and make little flat spots as the edges rub past each other and break off.
I prefer small flat ceramic stones for this work. medium and fine grades are good. If you use diamond it had better be very fine grit.
We have not started sharpening yet, get your strops figured out first if you can.
This is how we remove the sharpening burr and make the scissors full sharp.