When you recite anything that is meant to combat evil eye, your eyes will start watering, and you will start slumbering. This is an easy way to find it out! Finding such things is usually difficult for Novice, but gradually, you' d be shown how to know it! In the most intense cases, the hands of the reciter starts twisting! Even the neck and the entire body may start twisting. You should understand that it all depends on your Qalbi Haal ie Your spiritual state. Status with Allah matters...