no problem. When you will be building ngspice, as you will see in the INSTALL file, you will create a 'release' directory. Inside the directory you will need to run the following configure:

../configure  --with-x --enable-xspice --disable-debug --enable-cider --with-readline=yes --enable-openmp

This will install (after doing make and make install) ngspice into /usr/local/bin. If you need yto install in your home directory (/home/juan/bin) add

--prefix=/home/juan

to configure.