Hold the swollen finger under the faucet with cold water for 5-7 minutes, then lift your hand up and sit for about five minutes. During this time, the swelling should gradually come down, and the ring comes off with a finger.
In a jar with cold water, sprinkle in a few teaspoons of salt. Dip your finger in the resulting salt solution for 5 minutes. The tumor in this case should be slightly reduced, then you can try to remove the ring.
Take a thick thread about a meter long (preferably silk) and a needle. Pass the short thread end under the ring towards the base of the finger. To do this, insert a thread in the eye of a needle, slip the needle forward under the ring eyelet and pull a little fragment of the thread to the base of the finger. Next, the rest of the thread, wrap your finger so that between rows is left gaps. The finger has to be wrapped thread at the tip. Then grasp the short fragment of the thread, which remained at the base of the finger, and start unwinding its helical movements. The ring should easily withdraw from the finger.
If none of the above solutions work, you can only cut it ring. Do not do this at home, as you can go without a finger. Ask for help in the emergency room, or to rescue officers.
Currently very popular tungsten rings, but they are almost impossible to saw. If you can not remove a ring on their own, there is one option - to catch a finger with a ring in a vise and compress them up until the ring snaps. Finger will not suffer because tungsten rings can not be bent.
In any case, do not worry about the ring - the finger is much more expensive. Restore sliced decoration will help you in the jewelry workshop, as well as extend it to the desired size.