CUDA 7.5 installation on windows 10(64 bit) with nvidia geforce 940M

I have tried to install cuda 7.5 . I followed all the steps given in the documentation but it did not work. now I have reinstall my os and I wish to start once again pl.guide me

Follow the instructinos in the windows install guide:

http://docs.nvidia.com/cuda/cuda-installation-guide-microsoft-windows/index.html#abstract

except that you should deselect the driver install. Keep the driver that is already installed for your GPU.