Just as you need to complete forms when you leave, you will need to fill in forms when you return. The easiest way is to contact the consulate where you are registered to sort out your situation. You will have to establish a fully detailed inventory of your furniture. A moving form attestation is often demanded when you pass the border (you can ask for it at your Consulate).
You will have to think about school registration if you have children. A number of expatriation contracts come complete with a repatriation deal as well. If this is the case, it will be handy to set some time aside with a professional to help you adjust to relocating back to your home country and also help in transferring the experience back to your local colleagues.