Start by examining every check you can give. There are three: BxR (leads to RxB); Qg7 (leads to QxQ); and Qh8 (leads to KxQ). This last sequence is the most interesting one. Why? Because it forces the king to move, which often creates new tactical openings. Here it results in the Black king and queen and White knight all being left on dark squares; there is a fork at f7. But wait: what is Black’s reply to 2. NxR+? He can play Ra7xN, in effect trading a rook for White’s queen and knight! The problem for White, of course, is that the forking square (f7) isn’t safe. We have ways of handling that, however: here, start by taking the piece on the forking square in some other way and see if the piece that replaces it after a recapture might then be loose. Hence White plays 1. BxR, RxB; then comes 2. Qh8+, KxQ; 3. NxR+, forking and then taking Black's queen. White wins a queen and two rooks in return for a queen and a bishop.