Loose piece alert: Black has one on g4. Study whether you can attack it while also attacking Black’s king or threatening mate at the same time. These investigations lead you to Qxe6+, a rough draft of a queen fork. But of course you first would need to chase away the guard of the forking square, Black’s queen. You have one way to attack it: Rc7. Flush attacks like this should come easily to you now; the problem with this one, though, is that White loses the rook to QxR and doesn’t quite make up for it with the fork. Think, “if only the rook had protection when it jumped to c7. It almost does; if the pawn on b5 were one square closer…” So now you have a new goal: get your b-pawn forward one square. You can’t play it to b6 now because Black just takes it with his own pawn on a7. But if the a7 pawn were replaced with a Black piece you could push your b-pawn forward with a threat. At last the winning idea comes into view: 1. Bxa7, RxB; 2. b5-b6. Black moves his rook, probably to a6. Now you are ready to safely play 3. Rc7, Qe8; 4. Qxe6+, Qf7 (interposing); 5. QxN (at last), Rxb6 (Black takes the annoying pawn—this was why he played his rook to a6 on his second move).
For all this trouble, what has White won? A pawn. And the pawn is won even more simply if Black sees all this coming and simply declines to recapture after 1. Bxa7. Well, sometimes that’s chess: it can take a lot of work to win a pawn.