Use a steel strainer. Keep water in a small bowl.
Heat oil for frying.
Dip your fingers in water & spread a small patch on back of the strainer.
On this patch quickly, put a blob of batter.
Dip 1 finger in water and make small hole into the blob.Immediately turn the strainer on the wok (close to the level of oil) & allow the batter to fall into the oil.
Ensure that the distance is right - not to far as to cause splash of hot oil or close enough to fry the vada while being stuck to strainer.