The following shell commands install GStreamer for an unprivileged user, not system-wide. Adapt INSTALLDIR for your purposes. The GStreamer binaries will be installed into $INSTALLDIR/bin. Normally you would set INSTALLDIR to your home directory (you need to specify it as an absolute path). Consider adding $INSTALLDIR/bin to your PATH environment variable. After installation, check the outputs of which gst-launch-1.0 and gst-launch-1.0 --version, to see if you are using the correct binaries.
All following shell commands should be run as an unprivileged user, with the exception of apt-get install's. I have included installation instructions of as many external dependencies as possible to maximize the number of GStreamer plugins built. You may want to use only a subset of them. I may have forgotten some external dependencies, in which case the compilation should not fail, but simply the corresponding plugin skipped. Check the last output lines of each autogen.sh run to see which plugins will