Vastu Shastra experts recommends to use Light and soothing colors in general for a calming and relaxing mind. Avoid black or deep shades of colors as it might cause depression or strain to watch. You can pick different colors for each room as well for getting the best out it.
The perfect alignment can vary from house to house and as per individual requirements, thus you should always consult an expert for it. But in general, the following orientation is considered as the most suitable-
Master bedroom in SW
Living room in NE
Guest bedroom / kid’s room in NW
Kitchen in SE
Bathrooms in NW corners
Yantras or vastu tools are specially designed devices to radiate positive energy around it. These are of different types to attain better health, finance, harmony and so on. some of the vastu items or yantras are vastu pyramid, Hanumanji statue/poster, laughing buddha, swastika, om etc. your vastu expert can guide which yantra is suitable for you.
Worshiping regularly helps to build positive energy in a house. But it is not a replacement for vastu shastra as both of them has its own significance. Since vastu defect of a house builds negativity 24X7, worshiping alone is not adequate, you need to reinforce your guard against it with the help of vastu shastra.