One can persuade his dick to grow, not force it to as fighting against one’s self can only lead to ego’s defeats.
In my opinion, if you want to dedicate about one hour a day to hanging, you should accurately read HANGING 101 bearing in mind that that is about the best way to go about hanging for a beginner.
Also, unless you have a good friend who can teach you PERSONALLY how to wrap, you should dedicate much time and effort to learn how to wrap properly, as that (together with excess weight) is the most likely reason why your penis becomes dark and cold after a session.
If, for some reasons, you feel that you can follow a different approach, then you might decide to start with two 20 minute sessions in the morning and another two at night by applying two or three pounds of weight and increase the weight by one pound every second week or so.
In this way, about nine months from today, you shall be able to hang up to 20 pounds without having suffered injuries and, very likely, you shall have experienced some good growth.