Complex sentence: On 12 May 2013 the record attendance at the stadium was set when 3,408 turned up to watch Salisbury beat Dover Athletic 3--2 in the play-off final to earn promotion back to the Conference Premier after two seasons in the Conference South.
Split into simpler sentences: On 12 May 2013 a new record attendance at the stadium was set when 3,408 spectators turned up to watch Salisbury beat Dover Athletic 3--2 in the Conference South play-off final. This win earned them promotion back to the Conference Premier, after two seasons in the Conference South.