Centerpieces can serve both as a decorative touch and a home ward. These can look as normal as necessary. A simple vase filled with flowers can serve as a ward. You'd place your protections on the item by way of blessing it. You can also add petitions with protective symbols and affirmations under these centerpieces.
Wards can be hidden in the home. Under floor boards and other spaces. I like to use protective symbols behind artwork in frames. The artwork need not be witchy or pagan in nature. One can use a family photo. This is a great method for broom closet practitioners.
Charms, stones and such:
Stones and other protective charms can be used. Historically many of these methods were used. A horseshoe over a door for example. In Catholic folk practice a palm is often used over a doorway. Protective stones by entrances and in other prominent places are an excellent protective means. These too can be blessed before use.
Liquids and salts:
Salt is often used to ward and protect the home. In corners and by entrances salt is a mineral which is strongly protective. Holy water is good for strong protections. These wards are shorter term and will have to be replenished and upkept. Centerpieces and charms can be used for longer term.
Decorative wards can get pretty creative and unique and add something nice to look at while at the same time protecting the home and hearth.
Currently aside from other long term protections, I have a couple of centerpieces which act both as wards, and as magical stations.
In example, one centerpiece is a pedestal with a censor atop. In the censor I burn protective herbal blends to combine magical work with warding.
Home warding has been part of daily living. In this modern time sometimes we forget this. It has been practiced historically for quite a while, and is a strong method of protection magic.