You can put up barriers by using black salt in windowsills and door ways. Use witches bells and other charms. Use bay leaves. Use sage, palo santo or eucaluptus and give the space a good smudge and say a smudge prayer, then follow that with a either a tibetan singing bowls or a bell to use the sound to cleanse the energy even healing music tones of youtube are good too. Put a besom above your door and under your bed.
You can also change the space energy by using feng shui principles too. Under the spell section of this site their is some good home blessing and defense magic spells. You could also make a witches jar too. You can also plant certain plants around your house for protection. Black tourmaline is good for defense.
Sorry im not sure any more specifics then that, hope that was helpful. And just for general energy protection as well can also use Bagwa mirrors (feng shui mirrors) are good too, evil eyes to protect against psychic attacks as well. Black tourmaline stone to wear, and doing bath or shower ritual to remove any negative energy that might be in your energy field.
here is a video that might help
