Ok well for me the "perfect sub" is just like the "perfect woman" different things to different people. Secondly there are really two distinct submissive groups, life submissives who are naturally sub at all times and in all aspects of life. Then there is the sexual submissive who is only sub "in the bedroom". The vast majority that I have known have been sexual subs, in daily life you wouldn't guess they have a sub side. I will assume that you fall into this second group and want to continue to have a "normal" vanilla life but work at becoming a sexual sub for a yet to be discovered Dom?
D&S is all about control, the Dom has control, you give it up to him. At a basic level this simply means doing as you're told, this can include punishments for disobedience but more commonly you will find that as you are seeking approval from your Dom disappointing him can be all the punishment you need. Your Dom will no doubt have rules he expects you to follow, these of course vary from Dom to Dom but may include things like what clothes you are to wear when you meet, if make up is allowed, if he wants a smooth hairless body, how you speak to him, when you are allowed to touch him and even when you are allowed to touch yourself. I am not one to demand total silence and would always perfer a sub ask politely rather guess if unsure about something.
I have never been into the 24/7 type D&S thing and never lived with a sub so I like to define a play session so she is well aware of when I expect her to be "sub". This can vary from a few hours to entire weekends, for the most part it is the entire time we are together however sometimes there is a need to define a "non-play" time such as the occasional meal out when we are just friends having dinner. This is simply my example, I hope it gives you some insight into how it can be. No doubt you will find something different but the basic foundation is always the same, control.
