Simple process of Gayatri Mantra Jap -
After getting fresh from he daily routine, sit on a piece of cloth made of wool or carpet made of kusha ( a kind of grass ) in a comfortable posture with erect spinal cord, facing east in a separate room or at any suitable place. Keep a picture of Gayatri in front of you. Then close your eyes and medidate on Devi Gayatri feeling that Devi Gayatri is sitting in front of you, she is sitting on the red colored lotus flower. She has a red colored rosary in her hand, she is wearing red clothes. She is studying the Rigved. Swan is her vehicle. Lord Braha worships her . She is known as Ved Mata. She has the power to fulfill the desires of the person who has full faith in her. I bow to that mother, I bow to Devi Gayatri.
After this meditation and feeling, repeat or chant the following Mantra at least 324 times ( three Malas), or 540 times ( five Malas). The more Jap you do, the better it is. While reciting or doing Jap, your lips and tongue should move but the volume of your voice should be so low that even the people sitting beside you would not be able to hear it.
The Mantra is -
Om Bhoorbhuvah Svah tatsaviturvarenyam bhargo devasya dheemahi dhiyo yo nah prachodayaat.
ॐ भूर्भुवः स्वः तत्स वितुर्वरेण्यं भर्गो देवस्य धीमहि धियो यो नः प्रचोदयात।
When the Mantra Jap is over, do not leave the place of Puja immediately. After the Mantra Jap, sit very quietly, close your eyes and reflect on the infinitive love of goddess Gayatri. Have a felling in your mind that goddess gayatri is pouring her blessings upon you. She is fulfilling your wishes. She is leading you to the right path in the right direction.
After it, fold your hands and pay your respects to goddess Gayatri and leave the place of Puja and commence your routine duties.