well it's my understanding that in jeet kuen do you don't have to have a belt ranking system but i'm sure alot or most schools do anyway. anyway i practice jeet kuen do and wing chun, and boxing, and if you want to know all about jeet kuen do i highly suggest the tao of jeet kuen do which is thoughts from bruce lee put together in a book, and also i have found the tao of gung fu very helpful also which is another book that is bruce lee's thoughts and teachings on martial arts. i would buy those books if i was you and read them over and over again until you have a basic mental understanding of jeet kuen do then practice and practice but don't over strain yourself it's not worth a life full of pain so you most be careful and when you train you should do so little by little and balance everything evenly so that you don't over work your body and injure it. after maybe six months to a year you can start training harder because then your body will be stronger and conditioned to some extent. jeet kuen do is about many things but i would say that one of the main idea's of it is to be able to adapt to anything. another idea in jkd is only taking what works good for you and forgettng everything else, so basicly add and subject and keep doing so and you will keep the technic that works and not the one that is ineffective. it's about adaption, effectiveness, and process. adaption because you want to be able to adapt to anything and be able to fight well in anyway you have to, effectiveness because you only want to use the technic that works best for you and in self defence, and process because jeet kuen do and life is a process that is always changging to work more effectivly with their enviornments.
forgive my spelling i'm not good at it. i hope i've helped. peace.