Navratri Vrat Vidhi as Navratri vrat and Navratri pooja is observed at by over billion Hindus across India and the world including in our home. It may be observed slightly differently at your home so you can use it as a reference.
Cleaning house and home temple: To start with if possible, clean the house as you are inviting the Goddess Mother in your house. You can specially clean your house temple and sprinkle Ganga water in it. Avoiding onions and garlic: My mother-in-law does not use any onion and garlic in any recipe, no matter other people are keeping fast or not. So try to use all the onions and garlic before the fast is starting.
Navratri Vrat: Many devotees keep fast on all nine days of Navratri. My mother has kept fast on all nine days through out her life. But now because of old age and falling health, she keeps Navratri vrat on first and last day. If somehow, its not possible for you to keep fast on all nine days then you can try that on each day one person of your family is keeping Navratri Vrat in the house.
Navratri Vrat Vidhi: Some people keep Navratri vrat on the first and last day (my mother-in-law used to do this for last few years). This year one brahmin lady told her that it is better to keep fast on last 2 days. As after the first day fast you have started eating again and then you are keeping fast on the last day. According to this brahmin lady, it is better to keep fast on last 2 days than on keeping fast on first and last day of Navratri pooja.
Potting Barley seeds: Many people grow ‘Khetri’ or Barley seeds during this period. For this they collect, clean mud from an auspicious or clean place. This mud is put in a earthen pot. Clean and wash the barley to remove any insects or impurities and soak them in water for 15 to 30 minutes and then put these barley or ‘jau’ on the top of mud.
Make a thin layer of mud on top of barley, so as to cover it. Don’t put too much mud otherwise barley will not grow and put just enough water to soak the barley. One red color string (mauli) of mata rani is tied to khetri pot. Khetri color: The progress of ‘khetri’ or barley is observed very keenly by the devotee and it is believed that the longer they grow in height, the better it is for your family’s fortune and well being. It is also related to the blessings or happiness of the Goddess on you.
Few people believe that instead of observing the height of khetri, we should look at the color of khetri. Yellow color khetri is not good whereas green color khetri is considered good. On the last day of Navratri vrat or pooja, the khetri is immersed in moving water body like river or even a pond. If there is no water body nearby to your house then you can put the khetri under pipal tree in a temple.

Navratri Pooja and Items
Mata rani ka shingar (cosmetics) – My mother keeps Navtri pooja items in the temple at home and whenever (any day of Navratri) she go to a city temple devoted to goddess then she offer these Navratri pooja shingar items in the temple. The Navratri pooja shingar items include red bangles, red chunri, red lipstick, bindi, mehendi, kajal, nail polish, anklets, mirror and sindhur.
Akhand diya: One diya or lamp is burned through out the nine days and care must be taken that there is enough ghee or oil in the diya all the time. It is Akhand jyoti (burning non-stop all the time for nine days). This akhand jyoti will destroy all the negativity in your house.
Ensure that the lamp/diya keeps on burning non stop. It should not extinguish in between. If it does then it won’t be considered Akhand. Great importance is paid to make sure that the diya has enough ghee and wick all the time.
Chunri: Along with this one red color chunri or cloth and one mature coconut is kept in the house temple. The thin edge of coconut should be towards the temple.
Kalash: One kalash (earthen or copper pot) is filled with water, 5 betel nuts or suparis, sugar, rice and a clean five rupees coin and is kept with all these pooja items. In the kalash, red color string of mata rani is tied and this kalash water is sprinkled in your house after the kanjak pooja on 8th or 9th day. You can also drink this water. This water is considered as charanamrit and is holy.
Navratri Pooja: After taking bath in the morning, aarti is done for Devi Maa and bhog is given to Maa in the form of dry fruits and nuts (5 types), milk, bananas, mishri or other fruits. You can also offer fresh flowers. After doing the Durga aarti or Durga pooja only, my mother-in-law takes the food.
The same aarti is done in evening time (sandhya kaal) too. Burning incense, dhoop etc is part of morning and evening pooja. Please refrain from tasting the food ingredients for bhog, while assembling or preparing the Navratri bhog.
Source and credits: Vegrecipesofindia