You will need
- Can opener
Take a tin can and rinse from the dust.
Put the jar on the table, put on its edge can opener.
Holding the knife with one hand, the second hit him from above. The Bank formed a hole.
Holding the jar in one hand, a second start to make gentle movements, clinging to one edge of the knife over the side banks, and the second cut through the cap of the can in a circle.
Cover cut a little before the end and bent upward.
In the absence of a special knife, a tin can, you can open a conventional knife. Also punch a hole in the Bank and cut the lid of the jar around the circle in the usual movements (like bread).