Sight it in the way you shoot it. If you shoot one handed standing sight it in that way. Two handed the same way.
It really doesn't matter the size of your groups. Lets look at an example.
Assume you want to sight your revolver in at 25 yards, standing with two hands.
Set your target out, and shoot 20 plus rounds at your target. Take the target down and draw a line from 12 to 6, and from 9 to three. Your target is now divided in 4 quarters.
Count the number of shots in each quarter. If most are in the upper left quarter adjust your sight toward the lower right.
Now do it all over. Shoot 20 more rounds, draw your lines and count the hits in each quarter.
Keep shooting and adjusting until you get an equal number of shots in each quarter...........now you're sighted in.
Once you get there start practicing your fundamentals until you get your groups smaller.
This works with rifles as well as hand guns. You'll get a better zero based on how you shoot. I don't walk around carrying a bench so I don't zero from a bench.