In regards to praatan maryada or rehatname there's no written account of how to agan bhet your kes, its all about love and satkaar, you have to be practical and respectful when doing agan bhet or jal parvah of your kes.
Here are a few basic steps you need to follow and some basic information. When hair is burnt it releases alot of odor so make sure the area that you agen bhet kes is well ventilated, and it should preferebly be outside. Gather some firewood, match sticks, and dried grass / leaves that will start the fire, the fire doesn't have to be too big, some singhs say you can add oil to the fire to make it last longer or bigger, once the fire is burnt gather all kes that have separated from your body and keep them nearby, do Japji Sahib or Chopai Sahib and do ardaas to ask Guru Sahib for agya, then place your kes in the fire, hair burn very quickly so you can use an item on which you can place your hair which can be put in the fire, after all kes have been agan bhet then one must do ardaas to ask for kes daan, and for forgiveness for any mistakes.
If there are any more steps one can do, please post.