Trade pawns in the center to open up diagonals. The fewer pawns there are in the center, the more scope your bishops will have. Aiming both of your bishops at the opponent's king also increases the chance for tactical and mating combinations. Remember, without pawns in the center, enemy knights won't be able to use a centralized outpost.
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[Event "rated untimed match"] [Site "?"] [Date "????.??.??"] [Round "?"] [White "Unknown"] [Black "Unknown589"] [Result "0-1"] [Annotator "David Hayes"] [BlackElo "0"] [FEN "4b1k1/p1p5/1p6/4N3/1P2QP2/2P1P3/P1K3P1/q7 b - - 0 1"] [SetUp "1"] [TimeControl "0"] [WhiteElo "0"] 1... Ba4+ 2. Kd3 Qd1+ 3. Kc4 b5+ 4. Kc5 Qd6# 0-1