Is a symbolic science. Take below considerations for your main door
1. Have single door or door with two pieces equal in length & width. This allows auspicious energy to flow in.
2. Avoid dust bins or garbage cans outside the door thereby avoiding positive energy to be converted to negative.
3. Have 'umbra' near main door. Stops prosperity to go outside & prevents evil energies from entering house.
4. Do not have main doors hanging loosely on rusty hinges
5. A ruler of 42.96 cm is used for making furniture. In royal houses this scale is used for designing furniture. This activates positive energy
6. Avoid geometric patterns and motifs on the main door
7. Avoid broken handles, loose, hanging handles on the main door.
8. Choose color and the paint on the main door carefully.
9. Remove broken tiles, torn picture of the god. Remove dried flowers from the door.
10. Ensure the door opens & closes smoothly.
11. Remove the picture of goddess Lakshmi from the main door.
12. Discard any stickers with words of wisdom.