Of course you need a good barbeque sauce recipe. You need to cook your sauce under sanitary conditions. You will need a pressure cooker to bottle your sauce to ensure that no bacteria get into your sauce. You will need to label your sauce for sale. You also may need a license to use your kitchen this way.
First, ensure that your bottling operation has all required food licensing and food handling permits. This is necessary even if you bottle the product in your own kitchen or a rented kitchen. Secondly, secure a source of your ingredients. Then process the ingredients and have them bottled. You may have to rent or buy a bottler.