We were all noobies once, and we grew bigger by reading a few pdfs. Coming here to learn about basics is just wasting peoples time.
Its your responsibility to read about proper techniques in the many PDF's that are available online.
TI comes to mind, I studied their documents alot.
But it can be summed up like this, keep ground loop as small/close as possibl, so a ground plane beneat a trace, and a ground via besides a via.
" when The positive electricity searches far away for its negative side, the field is big, and so is the radio emissions"