How can I use my brain upto 100 %...???

That is good question, our brain uses normally 80% of its functions, but the functions it uses is one, like hearing, you can develop and concentrate to use hear or sight for 100% but it is almost impossible to use 100% in all of them, you don't use only 7% I'm sorry to say, we use about 50% if you practice a lot and concentrate/relax