I would start with Kegels and jelqing. maybe add some edging and ballooning. After several months you could add some squeezes or Ulis.
lot of guys have claimed big girth gains from clamping, but quite a few guys have sustained injuries from clamping too. Some claim to have made permanent girth gains from pumping when combined with regular PE modalities, but other pumpers feel the gains are temporary. Some have gained base girth through hanging or use of an extender.
I would not suggest hanging or clamping for a newbie.