I wouldn't recommend any sort of poking or jabbing sharp objects into the roots. If you are growing a potted plant, you can lightly bend the sides in around the pot when the soil is mostly dry. Also the watering cycle will be key, water-day A, wait day B, wait day C. Oxygen will naturally creep into the soil doing this ( unless you have the soil packed in and there is no space, but that requires a huge absence of common sense ) you probably just watered it and it started packing down. So just make sure you aren't watering everyday this will drown the roots, and try applying quick but gentle pressure around the lining of the pot if aeration is a real concern. Good luck, and Jah Bless