Start, as ever, by reconnoitering: what captures do you have the power to make? White’s queen threatens the rook on c7. The rook’s only guard is the queen on e7. This means the Black queen lacks flexibility, which invites you to look for ways to exploit other squares the queen appears to protect. One would be to give check with 1. Nf6, where White’s queen pins the g7 pawn and thus gives the knight a safe berth. If Black plays QxN, then of course White has QxR and wins the exchange. But Black can avoid that outcome by instead moving his king to h8, so the question is what comes next. Since you just moved your knight, ask whether it has fresh forking prospects. This leads to the charming move 2. Ne8, attacking the rook on c7 a second time and also creating the startling mate threat Qxg7#. Black can extinguish the threat with QxN, but now comes the much-awaited 3. QxR—followed by 4. Qxa7 (after Black moves his b8 rook up the board; he can’t move it to a8 because White’s bishop covers the square). White wins the exchange and a pawn.
The only variation to worry about occurs after White plays 2. Ne8. Black doesn’t have to play QxN; he can block the mate threat with g7-g6. But this is much worse for him, because by failing to make a capture on that move he has left his rook on c7 attacked twice and guarded just once. So after White plays 3. NxR Black dares not recapture. White wins a whole rook, not just the exchange.
The trickiest part of the position is seeing the finisher Ne8, as knight moves to an opponent’s crowded back rank are not common. The way to ensure that you see such moves is simply to be vigilant in looking for forks anytime your knight is in enemy territory, and reinspecting for them after any move of the other side's pieces—especially his king.