It is difficult to solder the cell with home equipment. I used adhesive tape to stick the metal contacts to the cell, RED wire to +ve and BLACK/WHITE wire to -ve

You have to avoid the metal contacts from short circuit, adhesive tapes can help you

I didn't have the contracting tubes that fit the cell which is 2cm diameter. Remember the cut yellow shield in step1? Use it to cover the metal parts and reconnect the battery