A simple Vishnu Puja at home can be performed by lighting diya, doing aarti, offering Tulsi leaves and chanting of the mantra Om Namo Narayana Namah or Vishnu Sahasranama.
Select a calm and quite place.
Clean the place and then take a bath.
Place a photograph or idol or picture of Vishnu
Keep a lamp ready. Place some Tulsi leaves, flowers and fruits or sweets ready in a plate.
Pray to Ganesha.
Meditate for a few minutes to clear the mind of unwanted thoughts and to attain concentration.
Now light the lamp.
Meditate or pray to Srihar Vishnu.
Offer flowers – Tulsi leaves.
You can light incense or agarbathis (optional).
If needed you can ring the bell, while offering flowers. (optional)
Chant the shloka – Om Namo Narayana Namah.
Now offer fruits or any sweet or usual food prepared for the deity. You can sprinkle some water after making the offering.
You can meditate for a few minutes or read some shlokas or prayers dedicated to Vishnu like Vishnu Sahasranama, Vishnu Suktam, Purusha Suktam, Narayana Upanishad etc.
After the Puja remove the fruits and share it as ‘prasad’ with others.
After the puja, find some time to read the Srimad Bhagavad Purana.