how can i update my U9 GT 8gb in latest firmware

[bj2res]

hello guys can anyone here guide me on how can i update/upgrade my U9 GT 8gb

i have one here but my touch screen wont work

i have encountered it on my WMT2.1_88 android i have to update its firmware and my touch screen works perpectly

can any one guide me how to update my U9 firmware

thanks in advace