concentrating-and-breathing-techniques

i find that in concentrating on the flexing of the muscle ie the bicep when you do a bicep curl helps you to some extent,because then you can control the weight more(if you think to yourself i can really lift this weight,then most likely you can do it),also in terms of breathing i find that if you breath in while bringing the weight towards yourself and breath out as you lower or push the weight then you will remember how to breath properly.these techniques above have helped me to some extent in my routines(the above may not work for everyone some people may have other techniques that help them in there weight training routines).