This topic comes up a lot so I'm posting this. Depending on your beliefs and practices, you can adapt this. If anyone has suggestions for improvements please let me know.
-Clean the house. Change sheets, take out trash, etc. Sweep the floors and porches while seeing all things dark and negative going away from your home.
-Prepare a place where you can be alone and undisturbed.
-Do a grounding exercise. Connect with the earth by seeing roots coming from your feet into the ground. Then, connect with light above, bringing it down throughout your body and then radiating outward and around you.
-Do a meditation to clear all negative thoughts and energies. Metta meditation (loving-kindness) works well. Here is a link to an example from Ajahn Brahm: https://www.youtube.com/watch?v=CRHWU12 ... re=youtube
-Ask your guides and/or the archangels to know your intent and assist. Speak out loud if it is appropriate (no one around to freak out). If you are familiar with sacred space, make your circle or do LBRP, RC, etc...(This is where your particular beliefs come in.)
-State that all earth bound spirits or entities that do not belong need to continue their journey and follow the light. Tell them not to fear, that someone they know will the there to guide them. Explain to them that they no longer belong there. State that this is your space and their path continues elsewhere. Bid them farewell.
-Burn angelica, sage or cedar (depending on what you have) in each room, closet, and even around the house if you feel it will help. Envision a white light in each space while saying I cleanse this space of anything harmful. Open all doors and as many windows as you can.
-Envision the whole house in white light, then yellow, then electric blue. White purifies, yellow heals, blue seals and protects.
-Ask the angels/gaurdians to bless the house and those who dwell there and to prevent anything unhealthy or non-essential entities from returning.
-Give thanks and ground your energies by water or earth (wash your hands or touch the ground)
-Put salt at the doors and windows.
-Put the whole thing out of your mind. It is important to have no fear while doing this or afterwards. the spirits most likely mean no harm and are just lost or lingering. They might need help moving on. Some can be stubborn but none can hurt you.
Think happy thoughts Play music and let the light shine in. You most likely will need to repeat this several days in a row and then weekly for a while. It is very important to keep good energy and thoughts to prevent any negative influences. Other energies/influences come and go. Sometimes they just need help. It is common for entities to be drawn to empathic and clairvoyant people.
This was effective for me, but it did have to be repeated for a while.